{\rtf1\fbidis\ansi\deff0{\fonttbl{\f0\fnil\fcharset0 MS Sans Serif;}}
\viewkind4\uc1\pard\ltrpar\qr\lang1025\f0\fs20 Free On-line Dictionary of Computing
\par 
\par \tab FOLDOC is a searchable dictionary of acronyms, jargon,
\par \tab programming languages, tools, architecture, operating systems,
\par \tab networking, theory, conventions, standards, mathematics,
\par \tab telecoms, electronics, institutions, companies, projects,
\par \tab products, history, in fact anything to do with computing.
\par 
\par \tab Copyright 1993 by Denis Howe
\par 
\par \tab Permission is granted to copy, distribute and/or modify this
\par \tab document under the terms of the GNU Free Documentation
\par \tab License, Version 1.1 or any later version published by the
\par \tab Free Software Foundation; with no Invariant Sections, Front-
\par \tab or Back-Cover Texts.  A copy of the license is included in the
\par \tab section entitled "\{GNU Free Documentation License\}".
\par 
\par \tab Please refer to the dictionary as "The Free On-line Dictionary
\par \tab of Computing, http://www.foldoc.org/, Editor Denis Howe" or
\par \tab similar.
\par 
\par \tab The dictionary has been growing since 1985 and now contains
\par \tab over 13000 definitions totalling nearly five megabytes of
\par \tab text.  Entries are cross-referenced to each other and to
\par \tab related resources elsewhere on the net.
\par 
\par \tab Where \{LaTeX\} commands for certain non-\{ASCII\} symbols are
\par \tab mentioned, they are described in their own entries.  "\\" is
\par \tab also used to represent the Greek lower-case lambda used in
\par \tab\{lambda-calculus\}.  Cross-references to other entries look
\par \tab\{like this\}.  Note that not all cross-references actually lead
\par \tab anywhere yet, but if you find one that leads to something
\par \tab inappropriate, please let me know.  Dates after entries
\par \tab indicate when that entry was last updated.  They do not imply
\par \tab that it was up-to-date at that time.
\par 
\par \tab You can search the latest version of the dictionary by \{WWW\}
\par \tab (URL http://www.foldoc.org/).  If you find an entry that
\par \tab is wrong or inadequate please let me know.
\par 
\par \tab See \{Pronunciation\} for how to interpret the pronunciation
\par \tab given for some entries.
\par 
\par \tab (2000-05-18)
\par 
\par Acknowledgements
\par 
\par \tab Many thanks to the hundreds of \{contributors
\par \tab (contributors.html)\}, and especially to the \{Guest Editors
\par \tab (editors.html)\}, mirror site maintainers and the maintainers
\par \tab of the following resources from which some entries originate:
\par 
\par \tab Mike Sendall's STING Software engineering glossary
\par \tab <sendall@dxpt01.cern.ch>, 1993-10-13,
\par 
\par \tab Bill Kinnersley's \{Language List
\par \tab (http://cuiwww.unige.ch/langlist)\} v2.2, 1994-01-15,
\par 
\par \tab Mark Hopkins' catalogue of Free Compilers and Interpreters
\par \tab v6.4, 1994-02-28,
\par 
\par \tab The on-line hacker \{Jargon File\} v3.0.0, 1993-07-27,
\par 
\par \tab Internet Users' Glossary (RFC 1392, FYI 18), Jan 1993.
\par 
\par \tab John Cross's computer glossary, 1994-11-01.
\par 
\par \tab John Bayko's Great Microprocessors of the Past and Present,
\par \tab v4.0.0, 1994-08-18.
\par 
\par \tab\{Electronic Commerce Dictionary\}.
\par 
\par \tab (1997-08-01)
\par 
\par !
\par 
\par \tab\{exclamation mark\}
\par 
\par "
\par 
\par \tab\{double quote\}
\par 
\par %
\par 
\par \tab\{percent\}
\par 
\par ,
\par 
\par \tab\{comma\}
\par 
\par 0
\par 
\par \tab\{zero\}
\par 
\par 0/1 knapsack problem
\par 
\par \tab <application> The \{knapsack problem\} restricted so that the
\par \tab number of each item is zero or one.
\par 
\par \tab (1995-03-13)
\par 
\par 100BaseFX
\par 
\par \tab <networking> \{Fast Ethernet\} over \{optical fibre\}.
\par 
\par \tab (1998-03-23)
\par 
\par 100BaseT
\par 
\par \tab <networking> Any of several \{Fast Ethernet\} 100 \{MBps\}
\par \tab\{CSMA/CD\} standards for \{twisted pair\} cables, including:
\par \tab 100BaseTx (100 Mbps over two-pair \{Cat5\} or better cable),
\par \tab 100BaseT4 (100 Mbps over four-pair \{Cat3\} or better cable),
\par \tab 100BaseT2 (in committee; 100 Mbps over two-pair Cat3 or better
\par \tab cable).  All are standards (or planned standards) under \{IEEE\}
\par \tab\{802.3\}.
\par 
\par \tab (1997-01-07)
\par 
\par 100BaseTX
\par 
\par \tab <networking> The predominant form of \{Fast Ethernet\}.
\par \tab 100BaseTX runs over two pairs of wires in \{category 5\} cable.
\par 
\par \tab (1998-06-30)
\par 
\par 100BaseVG
\par 
\par \tab <networking> A 100 \{MBps\} \{Ethernet\} standard specified to run
\par \tab over four pairs of \{category 3\} \{UTP\} wires (known as voice
\par \tab grade, hence the "VG").  It is also called 100VG-AnyLAN
\par \tab because it was defined to carry both \{Ethernet\} and \{token
\par \tab ring\} \{frame\} types.
\par 
\par \tab 100BaseVG was originally proposed by \{Hewlett-Packard\},
\par \tab ratified by the \{ISO\} in 1995 and practically extinct by 1998.
\par 
\par \tab 100BaseVG started in the IEEE 802.3u committee as \{Fast
\par \tab Ethernet\}.  One faction wanted to keep \{CSMA/CD\} in order to
\par \tab keep it pure Ethernet, even though the \{collision domain\}
\par \tab problem limited the distances to one tenth that of \{10baseT\}.
\par \tab Another faction wanted to change to a polling architecture
\par \tab from the hub (they called it "demand priority") in order to
\par \tab maintain the 10baseT distances, and also to make it a
\par \tab\{deterministic\} \{protocol\}.  The CSMA/CD crowd said, "This is
\par \tab 802.3 -- the Ethernet committee.  If you guys want to make a
\par \tab different protocol, form your own committee".  The IEEE 802.12
\par \tab committee was thus formed and standardized 100BaseVG.  The
\par \tab rest is history.
\par 
\par \tab (1998-06-30)
\par 
\par 100VG-AnyLAN
\par 
\par \tab\{100BaseVG\}
\par 
\par 10base2
\par 
\par \tab <networking> (Or "cheapernet") The variant of \{Ethernet\} that
\par \tab uses thin \{coaxial\} cable (RG-58 or similar), as opposed to
\par \tab\{10base5\} cable.
\par 
\par \tab The "10" means 10 \{Mbps\}, "base" means "baseband" as opposed
\par \tab to \{radio frequency\} and "2" means a maximum single cable
\par \tab length of 200m.
\par 
\par \tab (1995-11-14)
\par 
\par 10base5
\par 
\par \tab <networking> An \{Ethernet\} network cabling specification
\par \tab operating at ten \{Mbps\}, "baseband" (as opposed to \{radio
\par \tab frequency\}), and with a maximum single cable length of 500
\par \tab metres.  This is normally carried on \{RG8\} cable.
\par 
\par \tab Compare \{10base2\}, \{10baseT\}.
\par 
\par \tab (2002-06-17)
\par 
\par 10baseT
\par 
\par \tab <networking> A variant of \{Ethernet\} which allows stations to
\par \tab be attached via \{twisted pair\} cable.
\par 
\par \tab (1995-01-24)
\par 
\par 120 reset
\par 
\par \tab <jargon> /wuhn-twen'tee ree'set/ (After 120 volts, US mains
\par \tab voltage) To cycle power on a computer in order to reset or
\par \tab unjam it.
\par 
\par \tab Compare \{Big Red Switch\}, \{power cycle\}.
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (1994-11-23)
\par 
\par 1-2-3
\par 
\par \tab\{Lotus 1-2-3\}
\par 
\par 1394
\par 
\par \tab\{High Performance Serial Bus\}
\par 
\par 1541
\par 
\par \tab\{Commodore 1541\}
\par 
\par 1581
\par 
\par \tab\{Commodore 1581\}
\par 
\par 16550
\par 
\par \tab <hardware> A version of the 16450 \{UART\} with a 16-byte \{FIFO\}
\par \tab buffer.  Now revised to the 16550A.
\par 
\par \tab (1995-01-24)
\par 
\par 16 bit
\par 
\par \tab <architecture, programming> Using \{words\} containing sixteen
\par \tab\{bits\}.  This adjective often refers to the number of bits
\par \tab used internally by a computer's \{CPU\}.  E.g. "The \{Intel 8086\}
\par \tab is a sixteen bit processor".  Its external \{data bus\} or
\par \tab\{address bus\} may be narrower.  The term may also refer to the
\par \tab size of an instruction in the computer's \{instruction set\} or
\par \tab to any other item of data.
\par 
\par \tab See also \{16-bit application\}.
\par 
\par \tab (1996-05-13)
\par 
\par 16-bit application
\par 
\par \tab <operating system> Software for \{MS-DOS\} or \{Microsoft
\par \tab Windows\} which originally ran on the 16-bit \{Intel 8088\} and
\par \tab\{80286\} \{microprocessors\}.  These used a \{segmented address
\par \tab space\} to extend the range of addresses from what is possible
\par \tab with just a 16-bit address.  Programs with more than 64
\par \tab kilobytes of code or data therefore had to waste time
\par \tab switching between \{segments\}.  Furthermore, programming with
\par \tab segments is more involved than programming in a \{flat address
\par \tab space\}, giving rise to \{warts\} like \{memory models\} in \{C\} and
\par \tab\{C++\}.
\par 
\par \tab Compare \{32-bit application\}.
\par 
\par \tab (1996-04-06)
\par 
\par 1802
\par 
\par \tab <processor> An 8-bit \{microprocessor\} currently manufactured
\par \tab as CDP1802 by \{HARRIS Semiconductor\}.  It has been around for
\par \tab ten years at least and is ideally suited for \{embedded\}
\par \tab applications.  Some of its features are: 8-bit parallel
\par \tab organisation with bidirectional \{data bus\} and \{multiplexed
\par \tab address bus\}; static design -- no minimum clock frequency;
\par \tab bit-programmable output port; four input pins which are
\par \tab directly tested by branch instructions; flexible programmable
\par \tab I/O mode; single-phase clock, with on-chip oscillator; 16 x 16
\par \tab register matrix to implement multiple \{program counters\},
\par \tab pointers, or \{registers\}
\par 
\par \tab (1995-11-21)
\par 
\par 1NF
\par 
\par \tab\{database normalisation\}
\par 
\par 1TBS
\par 
\par \tab One True Brace Style.
\par 
\par \tab See \{indent style\}.
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (1995-01-25)
\par 
\par 1.TR.6
\par 
\par \tab <networking, protocol> A \{control channel protocol\} for
\par \tab\{ISDN\}.  It is a national \{standard\} in Germany but is being
\par \tab replaced by \{Euro-ISDN\}.
\par 
\par \tab (1995-03-27)
\par 
\par 2
\par 
\par \tab <convention, character> In names of translation software,
\par \tab infix 2 often represents the word "to" with the connotation
\par \tab "translate to", as in \{dvi2ps\} (\{DVI\} to \{PostScript\}),
\par \tab int2string (integer to string) and \{texi2roff\} (\{Texinfo\} to
\par \tab [nt]\{roff\}).
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (1995-01-25)
\par 
\par 20-GATE
\par 
\par \tab <language> An algebraic language for the \{G-20\}, developed at
\par \tab\{Carnegie\} around 1965.
\par 
\par \tab (1995-02-27)
\par 
\par 2780
\par 
\par \tab\{Binary Synchronous Transmission\}
\par 
\par 2B1D
\par 
\par \tab\{Basic Rate Interface\}
\par 
\par 2B1Q
\par 
\par \tab\{two-binary, one-quaternary\}
\par 
\par 2B+D
\par 
\par \tab\{Basic Rate Interface\}
\par 
\par 2NF
\par 
\par \tab\{database normalisation\}
\par 
\par 2.PAK
\par 
\par \tab <language> An \{artificial intelligence\} language with
\par \tab\{coroutine\}s.
\par 
\par \tab ["The 2.PAK Language: Goals and Description", L.F. Melli, Proc
\par \tab IJCAI 1975].
\par 
\par \tab (1995-01-25)
\par 
\par 320xx
\par 
\par \tab <processor> A series of \{microprocessors\} from \{National
\par \tab Semiconductor\}.  The 320xx processors have a \{coprocessor\}
\par \tab interface which allows coprocessors such as \{FPU\}s and \{MMU\}s
\par \tab to be attached in a chain.
\par 
\par \tab The 320xx was the predecessor of the \{Swordfish\} processor.
\par 
\par \tab [Details?]
\par 
\par \tab (1994-11-17)
\par 
\par 3270
\par 
\par \tab\{IBM 3270\}
\par 
\par 32-bit application
\par 
\par \tab <architecture, operating system> \{IBM PC\} software that runs
\par \tab in a 32-bit \{flat address space\}.
\par 
\par \tab The term \{32-bit application\} came about because \{MS-DOS\} and
\par \tab\{Microsoft Windows\} were originally written for the \{Intel
\par \tab 8088\} and \{80286\} \{microprocessors\}.  These are \{16 bit\}
\par \tab microprocessors with a \{segmented address space\}.  Programs
\par \tab with more than 64 kilobytes of code and/or data therefore had
\par \tab to switch between \{segments\} quite frequently.  As this
\par \tab operation is quite time consuming in comparison to other
\par \tab machine operations, the application's performance may suffer.
\par \tab Furthermore, programming with segments is more involved than
\par \tab programming in a flat address space, giving rise to some
\par \tab complications in programming languages like "\{memory models\}"
\par \tab in \{C\} and \{C++\}.
\par 
\par \tab The shift from 16-bit software to 32-bit software on \{IBM PC\}
\par \tab\{clones\} became possible with the introduction of the \{Intel
\par \tab 80386\} microprocessor.  This microprocessor and its successors
\par \tab support a segmented address space with 16-bit and 32 bit
\par \tab segments (more precisely: segments with 16- or 32-bit address
\par \tab offset) or a linear 32-bit address space.  For compatibility
\par \tab reasons, however, much of the software is nevertheless written
\par \tab in 16-bit models.
\par 
\par \tab\{Operating system\}s like \{Microsoft Windows\} or \{OS/2\} provide
\par \tab the possibility to run 16-bit (segmented) programs as well as
\par \tab 32-bit programs.  The former possibility exists for \{backward
\par \tab compatibility\} and the latter is usually meant to be used for
\par \tab new software development.
\par 
\par \tab See also \{Win32s\}.
\par 
\par \tab (1995-12-11)
\par 
\par 3780
\par 
\par \tab\{Binary Synchronous Transmission\}
\par 
\par 386
\par 
\par \tab\{Intel 80386\}
\par 
\par 386BSD
\par 
\par \tab <operating system> A \{free software\} version of the \{BSD Unix\}
\par \tab\{operating system\} originally derived from the generally
\par \tab available parts of the "\{Berkeley Net Release/2\}".  William
\par \tab Jolitz played a key r\'f4le and there have been many
\par \tab contributors.  Many new and innovative features have been
\par \tab added to 386BSD since its original release in June 1992.  An
\par \tab unofficial patchkit, available from many \{anonymous FTP\}
\par \tab archives, solves many of the problems associated with 386BSD
\par \tab Version 0.1.  In addition, many common Unix packages have been
\par \tab ported.
\par 
\par \tab 386BSD has been superseded by \{FreeBSD\} and \{NetBSD\}.
\par 
\par \tab\{FAQ
\par \tab (http://www.cis.ohio-state.edu/hypertext/faq/usenet/386bsd-faq/part1/faq.html)\}.
\par 
\par \tab (1995-02-15)
\par 
\par 386SPART.PAR
\par 
\par \tab <operating system> (Or "\{WIN386.SWP\}") 386SPART.PAR is a
\par \tab\{hidden file\} created by \{Windows 3.1\} for use as \{virtual
\par \tab memory\} \{swap file\}.  It is generally found in the \{root
\par \tab directory\}, however it may appear elsewhere (typically in the
\par \tab WINDOWS directory).  Its size depends on how much virtual
\par \tab memory you have set up under (Control Panel) Enhanced under
\par \tab Virtual Memory.  If you move or delete this file Windows will
\par \tab complain the next time you start it with a Swap File error.
\par 
\par \tab\{Windows 95\} uses a similar file, except it is named
\par \tab WIN386.SWP, and the controls for it are located under Control
\par \tab Panel - System - Performance tab - Virtual Memory.
\par 
\par \tab (1996-05-28)
\par 
\par 3Com Corporation
\par 
\par \tab <company, networking> A manufacturer of \{local area network\}
\par \tab equipment.
\par 
\par \tab 3Com was founded in 1979.  They acquired \{BICC Data Networks\}
\par \tab in 1992, \{Star-Tek\} in 1993, \{Synernetics\} in 1993, \{Centrum\}
\par \tab in 1994, \{NiceCom\} in 1994 \{AccessWorks\}, \{Sonix
\par \tab Communications\}, \{Primary Access\} and \{Chipcom\} in 1995 and
\par \tab\{Axon\} and \{OnStream Networks\} in 1996.  They merged with
\par \tab\{U.S. Robotics\} in 1997.
\par 
\par \tab\{Home (http://www.3com.com/)\}.
\par 
\par \tab (1998-04-03)
\par 
\par 3DNow!
\par 
\par \tab <architecture> A \{floating point\} \{SIMD\} extention from \{AMD\}.
\par 
\par \tab [Extension of what?  To do what?]
\par 
\par \tab (2001-12-23)
\par 
\par 3DNow! Professional
\par 
\par \tab <architecture> A \{floating point\} \{SIMD\} extention from \{AMD\},
\par \tab compatible with \{Intel\}'s \{SSE\}, introduced with the
\par \tab\{Athlon\}-4.
\par 
\par \tab [Relationship to \{3DNow!\}?]
\par 
\par \tab (2001-12-23)
\par 
\par 3DO
\par 
\par \tab <company, games, standard> A set of specifications created and
\par \tab owned by the 3DO company, which is a partnership of seven
\par \tab different companies.  These specs are the blueprint for making
\par \tab a 3DO Interactive Multiplayer and are licensed to hardware and
\par \tab software producers.
\par 
\par \tab A 3DO system has an \{ARM60\} 32-bit \{RISC\} \{CPU\} and a graphics
\par \tab engine based around two custom designed graphics and animation
\par \tab processors.  It has 2 Megabytes of \{DRAM\}, 1 Megabyte of
\par \tab\{VRAM\}, and a double speed \{CD-ROM\} drive for main storage.
\par 
\par \tab The \{Panasonic\} 3DO system can run 3DO Interactive software,
\par \tab play audio CDs (including support for CD+G), view \{Photo-CD\}s,
\par \tab and will eventually be able to play \{Video CD\}s with a special
\par \tab add-on \{MPEG\}1 \{full-motion video\} cartridge.  Up to 8
\par \tab\{controller\}s can be \{daisy-chain\}ed on the system at once.  A
\par \tab keyboard, mouse, light gun, and other peripherals may also
\par \tab some day be hooked into the system, although they are not
\par \tab currently available (December 1993).  The 3DO can display
\par \tab\{full-motion video\}, fully \{texture map\}ped 3d landscapes,
\par \tab all in 24-bit colour.  \{Sanyo\} and \{AT&T\} will also release
\par \tab 3DO systems.  Sanyo's in mid 1994 and AT&T in late 1994.
\par 
\par \tab There will be a 3DO add-on cartridge based on the \{PowerPC\} to
\par \tab enable the 3DO to compete with \{Sony\}'s \{Playstation\} console
\par \tab and \{Sega\}'s \{Saturn\} console, both of which have a higher
\par \tab specification than the original 3DO.  The add-on is commonly
\par \tab known as the M2 or Bulldog.  It should hit the shops by
\par \tab Christmas 1995 and will (allegedly) do a million flat shaded
\par \tab polygons per second.
\par 
\par \tab\{3DO Home (http://www.3do.com/)\}.
\par 
\par \tab\{Usenet\} newsgroup: \{news:rec.games.video.3do\}.
\par 
\par \tab (1994-12-13)
\par 
\par 3GL
\par 
\par \tab\{third generation language\}
\par 
\par 3NF
\par 
\par \tab\{database normalisation\}
\par 
\par 3Station
\par 
\par \tab <computer, networking> The archetypal \{diskless workstation\},
\par \tab developed by \{Bob Metcalfe\} at \{3Com\} and first available in
\par \tab 1986/1987.
\par 
\par \tab The 3Station/2E had a 10 \{MHz\} \{80286\} \{processor\}, 1 \{MB\} of
\par \tab\{RAM\} (expandable to 5 MB), \{VGA\} compatible graphics with 256
\par \tab\{KB\} of \{video RAM\}, and integrated \{AUI\}/\{BNC\} network
\par \tab\{transceivers\} for \{LAN\} access.
\par 
\par \tab The product used a single \{printed-circuit board\} with four
\par \tab custom \{ASICs\}.  It had no \{floppy disk drive\} or \{hard disk\},
\par \tab it was booted from a \{server\} and stored all \{end-user\}
\par \tab\{files\} there.
\par 
\par \tab 3Com advertised "significant cost savings" due to the
\par \tab 3Station's ease of installation and low maintenance (this
\par \tab would now be referred to under the banner of "\{TCO\}").
\par 
\par \tab The 3Station cost somewhere between an \{IBM PC\} \{clone\} and an
\par \tab IBM PC of the day.  It was not commercially successful.
\par 
\par \tab (2000-07-05)
\par 
\par 3-tier
\par 
\par \tab\{three-tier\}
\par 
\par 404
\par 
\par \tab <abuse> Someone who's clueless.  From the \{World-Wide Web\}
\par \tab message "404, URL Not Found" meaning that the document you've
\par \tab tried to access can't be located.
\par 
\par \tab "Don't bother asking him...he's 404, man".
\par 
\par \tab 404 is one of the standard response codes of the \{telnet\}
\par \tab\{protocol\} on which the web's \{HTTP\} is based.
\par 
\par \tab The first 4 indicates a client error such as a mistyped URL.
\par \tab The middle 0 refers to a general syntax error.  The last 4
\par \tab just indicates the specific error in the group of 40x, which
\par \tab also includes 400: Bad Request, 401: Unauthorized, etc.
\par 
\par \tab (2000-03-18)
\par 
\par 4.2BSD
\par 
\par \tab\{Berkeley System Distribution\}
\par 
\par 431A
\par 
\par \tab <hardware> The type of plug which fits a standard "type 600"
\par \tab\{British Telecom\} telephone socket.
\par 
\par \tab (1995-01-25)
\par 
\par 4510
\par 
\par \tab <processor> A \{65CE02\} with two \{6526\}s.
\par 
\par \tab Used in the \{Commodore 65\}.
\par 
\par \tab (1996-04-06)
\par 
\par 473L Query
\par 
\par \tab <language> An English-like \{query language\} for the US Air
\par \tab Force \{473L\} system.
\par 
\par \tab [Sammet 1969, p. 665].
\par 
\par \tab ["Headquarters USAF Command and Control System Query
\par \tab Language", Info Sys Sci, Proc 2nd Congress, Spartan Books
\par \tab 1965, pp.57-76].
\par 
\par \tab (1994-10-31)
\par 
\par 486
\par 
\par \tab\{Intel 486\}
\par 
\par 486SX
\par 
\par \tab\{Intel 486SX\}
\par 
\par 4GL
\par 
\par \tab\{fourth generation language\}
\par 
\par 4NF
\par 
\par \tab\{database normalisation\}
\par 
\par 51forth
\par 
\par \tab <language> A subroutine-\{threaded\} \{Forth\} for the \{8051\} by
\par \tab Scott Gehmlich.  It comes with source and documentation.
\par 
\par \tab\{(ftp://smis-novell-1.massey.ac.nz/giovanni/51forth.zip)\}
\par 
\par \tab (1993-04-03)
\par 
\par 56 kbps
\par 
\par \tab <communications> (56 kilobits per second) The data capacity of
\par \tab a normal single channel digital telephone channel in North
\par \tab America.  The figure is derived from the \{bandwidth\} of 4 kHz
\par \tab allocated for such a channel and the 16-bit encoding (4000
\par \tab times 16 = 64000) used to change \{analogue\} signals to
\par \tab digital, minus the 8000 bit/s used for signalling and
\par \tab supervision.
\par 
\par \tab At the end of 1997 there were two rival \{modem\} designs
\par \tab capable of this rate: \{k56flex\} and \{US Robotics\}' \{X2\}.  In
\par \tab February 1998 the \{ITU\} proposed a 56kbps standard called
\par \tab\{V.90\}, which is expected to be formally approved during
\par \tab September 1998.
\par 
\par \tab (1998-09-15)
\par 
\par 56k line
\par 
\par \tab <communications> A digital connection (possibly a \{leased
\par \tab line\}, possibly switched) capable of carrying \{56 kbps\}.
\par 
\par \tab Compare \{DS0\}.
\par 
\par \tab (2000-07-16)
\par 
\par 586
\par 
\par \tab <processor> What \{Intel\}'s \{Pentium\} was not called.
\par 
\par 5ESS Switch
\par 
\par \tab <communications> The class 5 electronic switching system sold
\par \tab by \{Lucent Technologies\}.  The 5ESS Switch is the digital
\par \tab\{central office\} \{circuit switching\} system many communication
\par \tab\{service providers\} use.
\par 
\par \tab (2001-07-12)
\par 
\par 5NF
\par 
\par \tab\{database normalisation\}
\par 
\par 5th Glove
\par 
\par \tab <hardware, virtual reality> A \{data glove\} and flexor strip
\par \tab kit (5th Glove DFK) sold by \{Fifth Dimension Technologies\} for
\par \tab $495 ($345 for the left-handed version, $45 for each extra
\par \tab flexor strip).  The DFK provides a data glove, a flexon strip
\par \tab (with an elbow or knee-joint sensor), an interface card,
\par \tab cables, and KineMusica software.  The package uses flexible
\par \tab optical-bending sensing to track hand and arm movement.  The
\par \tab glove can be used with 5DT's ultrasonic tracking system, the
\par \tab 5DT Head and Hand tracker ($245), which can track movement
\par \tab from up to two metres away from the unit's transmitter.
\par 
\par \tab (1998-02-06)
\par 
\par 6.001
\par 
\par \tab <education> /siks dub*l oh wun/, /dub*l oh wun/ or rarely
\par \tab /siks dub*l oh fun/ \{MIT\}'s introductory computer class for
\par \tab majors, known for its intensity.  Developed by \{Gerald
\par \tab Sussman\} and \{Hal Abelson\}, the course is taught in \{Scheme\}
\par \tab and introduces \{recursion\}, \{higher-order function\}s,
\par \tab\{object-oriented programming\} and much more.  Students who
\par \tab grasp the \{meta\}circular \{interpreter\} gain entry into the
\par \tab\{Knights of the Lambda-Calculus\}.  6.001 has been exported to
\par \tab several other colleges, sometimes successfully.  The textbook,
\par \tab "Structure and Interpretation of Computer Programs", written
\par \tab with Julie Sussman is a classic that can be found on the
\par \tab shelves of many computer scientists, whether they took the
\par \tab course or not.  Legendary characters from the class, problem
\par \tab sets, and book include the wise Alyssa P. Hacker, Ben
\par \tab Bitdiddle, Lem E. Tweakit and Eva Lu Ator, the careless Louis
\par \tab Reasoner and \{Captain Abstraction\}.
\par 
\par \tab (1994-11-22)
\par 
\par 610
\par 
\par \tab <communications> The standard type of two-wire wall socket and
\par \tab plug used for telephones in Australia.
\par 
\par \tab [Other countries?  Full name?]
\par 
\par \tab (1997-06-26)
\par 
\par 6309
\par 
\par \tab\{Hitachi 6309\}
\par 
\par 64 bit
\par 
\par \tab <architecture> A term describing a computer architecture based
\par \tab around an \{ALU\}, \{registers\}, and \{data bus\} which are 64
\par \tab\{bit\}s wide.
\par 
\par \tab 64-bit processors are quite common in 1996, e.g. \{Digital\}
\par \tab\{Alpha\}, versions of \{Sun\} \{SPARC\}, \{MIPS\}, \{IBM\} \{AS/4000\}.
\par \tab the \{PowerPC\} and \{Intel\} are expected to move to 64 bits at
\par \tab their next generation - \{PPC 620\} and \{Intel P7\}.
\par 
\par \tab A 64-bit \{address bus\} allows the processor to address 18
\par \tab million \{gigabytes\} as opposed to the mere 4 gigabytes allowed
\par \tab with 32 bits.  There are in 1996 already \{hard disks\} which
\par \tab can hold over 4GB.  Floating point calculations can also be
\par \tab more accurate.
\par 
\par \tab A 64-bit \{OS\} is needed as well to take advantage of the CPU.
\par \tab In 1986 there are only a few 64-bit operating systems,
\par \tab including \{OS/400\}, \{Digital\} \{Unix\}, \{Solaris\} (partialy).  A
\par \tab 32-bit OS can run on a 64-bit CPU.
\par 
\par \tab (1996-12-23)
\par 
\par 6501
\par 
\par \tab <hardware> An eight-bit \{microprocessor\}, the first sold by
\par \tab\{MOS Technologies\}.  The 6501 pin-compatible with the
\par \tab\{Motorola 6800\} and was the first member of the 650x series.
\par \tab It had had an on-chip clock oscillator.
\par 
\par \tab See also \{6502\}.
\par 
\par \tab (2001-02-26)
\par 
\par 6502
\par 
\par \tab <hardware> An eight-bit \{microprocessor\} designed by \{MOS
\par \tab Technologies\} around 1975 and made by \{Rockwell\}.
\par 
\par \tab Unlike the \{Intel 8080\} and its kind, the 6502 had very few
\par \tab\{registers\}.  It was an 8-bit processor, with 16-bit \{address
\par \tab bus\}.  Inside was one 8-bit data register (\{accumulator\}), two
\par \tab 8-bit \{index registers\} and an 8-bit \{stack pointer\} (stack
\par \tab was preset from address 256 to 511).  It used these index and
\par \tab stack registers effectively, with more \{addressing modes\},
\par \tab including a fast zero-page mode that accessed memory locations
\par \tab from address 0 to 255 with an 8-bit address (it didn't have to
\par \tab fetch a second byte for the address).
\par 
\par \tab Back when the 6502 was introduced, \{RAM\} was actually faster
\par \tab than \{CPU\}s, so it made sense to optimize for RAM access
\par \tab rather than increase the number of registers on a chip.
\par 
\par \tab The 6502 was used in the \{BBC Microcomputer\}, \{Apple II\},
\par \tab\{Commodore\}, \{Apple Computer\} and \{Atari\} \{personal
\par \tab computers\}.  \{Steve Wozniak\} described it as the first chip
\par \tab you could get for less than a hundred dollars (actually a
\par \tab quarter of the \{6800\} price).
\par 
\par \tab The 6502's \{indirect jump\} instruction, JMP (xxxx), was
\par \tab\{broken\}.  If the address was hexadecimal xxFF, the processor
\par \tab would not access the address stored in xxFF and xxFF + 1, but
\par \tab rather xxFF and xx00.  The \{6510\} did not fix this bug, nor
\par \tab was it fixed in any of the other \{NMOS\} versions of the 6502
\par \tab such as the \{8502\}.  Bill Mensch at \{Western Design Center\}
\par \tab was probably the first to fix it, in the \{65C02\}.
\par 
\par \tab The 6502 also had undocumented instructions.
\par 
\par \tab The \{65816\} is an expanded version of the 6502.
\par 
\par \tab There is a 6502 \{assembler\} by Doug Jones <jones@cs.uiowa.edu>
\par \tab which supports \{macros\} and conditional features and can be
\par \tab used for linkage editing of object files.  It requires
\par \tab\{Pascal\}.
\par 
\par \tab See also \{cross-assembler\}, \{RTI\}, \{Small-C\}.
\par 
\par \tab (2001-01-02)
\par 
\par 650x
\par 
\par \tab <hardware> A family of \{microprocessor\}s from \{MOS
\par \tab Technologies\}, based on the design of the \{Motorola 6800\}
\par \tab (introduced around 1975).  The family included the \{6502\} used
\par \tab in several early \{personal computer\}s.
\par 
\par 6510
\par 
\par \tab <processor> A successor to the \{6502\}.
\par 
\par \tab The 6510 was used in the Commodore 64C.  Successors included
\par \tab the \{8502\} used in the \{Commodore 128\} line.
\par 
\par \tab (2001-01-02)
\par 
\par 65816
\par 
\par \tab <processor> An expanded version of the \{6502\}, with which it
\par \tab is compatible.  It has 16-bit \{index register\}s and \{stack
\par \tab pointer\}, a 16-bit direct page register and a 24-bit \{address
\par \tab bus\}.  Used in later models of the \{Apple II\}.
\par 
\par \tab (1994-10-31)
\par 
\par 6800
\par 
\par \tab\{Motorola 6800\}
\par 
\par 68000
\par 
\par \tab\{Motorola 68000\}
\par 
\par 68020
\par 
\par \tab\{Motorola 68020\}
\par 
\par 68030
\par 
\par \tab\{Motorola 68030\}
\par 
\par 68040
\par 
\par \tab\{Motorola 68040\}
\par 
\par 68050
\par 
\par \tab\{Motorola 68050\}
\par 
\par 68060
\par 
\par \tab\{Motorola 68060\}
\par 
\par 6809
\par 
\par \tab\{Motorola 6809\}
\par 
\par 680x0
\par 
\par \tab\{Motorola 680x0\}
\par 
\par 686
\par 
\par \tab <processor> \{Pentium Pro\} or possibly \{Cyrix 6x86\}.
\par 
\par \tab (1997-05-26)
\par 
\par 68HC11
\par 
\par \tab\{Motorola 68HC11\}
\par 
\par 68LC040
\par 
\par \tab\{Motorola 68LC040\}
\par 
\par 6x86
\par 
\par \tab\{Cyrix 6x86\}
\par 
\par 754
\par 
\par \tab\{IEEE Floating Point Standard\}
\par 
\par 80186
\par 
\par \tab\{Intel 80186\}
\par 
\par 80188
\par 
\par \tab\{Intel 80188\}
\par 
\par 802.2
\par 
\par \tab\{IEEE 802.2\}
\par 
\par 802.3
\par 
\par \tab\{IEEE 802.3\}
\par 
\par 80286
\par 
\par \tab\{Intel 80286\}
\par 
\par 8031
\par 
\par \tab\{Intel 8051\}
\par 
\par 80386
\par 
\par \tab\{Intel 80386\}
\par 
\par 8048
\par 
\par \tab\{Intel 8048\}
\par 
\par 80486
\par 
\par \tab\{Intel 486\}
\par 
\par 8051
\par 
\par \tab\{Intel 8051\}
\par 
\par 8052
\par 
\par \tab\{Intel 8051\}
\par 
\par 8080
\par 
\par \tab\{Intel 8080\}
\par 
\par 8086
\par 
\par \tab\{Intel 8086\}
\par 
\par 8088
\par 
\par \tab\{Intel 8088\}
\par 
\par 80x86
\par 
\par \tab\{Intel 80x86\}
\par 
\par 822
\par 
\par \tab\{RFC 822\}
\par 
\par 82430FX
\par 
\par \tab\{Triton I\}
\par 
\par 82430HX
\par 
\par \tab\{Triton II\}
\par 
\par 82430MX
\par 
\par \tab\{Mobile Triton\}
\par 
\par 82430VX
\par 
\par \tab\{Triton VX\}
\par 
\par 8.3
\par 
\par \tab <file system, filename extension> A common shorthand for the
\par \tab limits on filename length imposed by the \{file system\} used by
\par \tab\{MS-DOS\} and \{Microsoft Windows\} - at most eight characters,
\par \tab followed by a ".", followed by a \{filename extension\} of at
\par \tab most three characters.
\par 
\par \tab\{Windows 95\} supports long filenames by using multiple
\par \tab directory entries per file.  The extra entries are hidden.  It
\par \tab also automatically derives an 8.3 name for each file for
\par \tab\{backward compatibility\} so that older versions of DOS can
\par \tab still access the file.
\par 
\par \tab (1998-10-05)
\par 
\par 8514
\par 
\par \tab <hardware> An \{IBM\} graphics \{display standard\} supporting a
\par \tab\{resolution\} of 1024 x 768 \{pixels\} with 256 colours at 43.5
\par \tab Hz (\{interlaced\}), or 640 x 480 at 60 Hz interlaced.
\par 
\par \tab 8514 was introduced at the same time as \{VGA\} and was
\par \tab superseded by \{XGA\}.
\par 
\par \tab (1999-08-01)
\par 
\par 8514-A
\par 
\par \tab\{8514\}
\par 
\par 88000
\par 
\par \tab\{Motorola 88000\}
\par 
\par 88open
\par 
\par \tab <body> A consortium with the aim of creating a multi-vendor
\par \tab open computing environment based on the \{Motorola 88000\}
\par \tab\{RISC\} processor family.
\par 
\par \tab (1995-01-26)
\par 
\par 8-bit clean
\par 
\par \tab\{eight-bit clean\}
\par 
\par 8N1
\par 
\par \tab <jargon> Common shorthand for "eight data bits, no \{parity\},
\par \tab one \{stop bit\}", the most common configuration for \{serial
\par \tab line\}s, e.g. \{EIA-232\}.
\par 
\par \tab (1995-01-31)
\par 
\par 8 queens problem
\par 
\par \tab\{eight queens puzzle\}
\par 
\par 8 queens puzzle
\par 
\par \tab\{eight queens puzzle\}
\par 
\par 8x86
\par 
\par \tab\{Intel 80x86\}
\par 
\par 90-90 Rule
\par 
\par \tab\{Ninety-Ninety Rule\}
\par 
\par 9PAC
\par 
\par \tab <tool> 709 PACkage.
\par 
\par \tab A \{report generator\} for the \{IBM 7090\}, developed in 1959.
\par 
\par \tab [Sammet 1969, p.314. "IBM 7090 Prog Sys, SHARE 7090 9PAC Part
\par \tab I: Intro and Gen Princs", IBM J28-6166, White Plains, 1961].
\par 
\par \tab (1995-02-07)
\par 
\par :-)
\par 
\par \tab\{emoticon\}
\par 
\par ;
\par 
\par \tab\{semicolon\}
\par 
\par =
\par 
\par \tab\{equals\}
\par 
\par @
\par 
\par \tab\{commercial at\}
\par 
\par A#
\par 
\par \tab <language> /A sharp/ A separable component of Version 2 of the
\par \tab\{AXIOM*\} computer algebra system.  It provides a programming
\par \tab language with an \{optimising compiler\}, an \{intermediate code\}
\par \tab\{interpreter\}, and a library of data structures and
\par \tab mathematical \{abstraction\}s.  The compiler produces
\par \tab\{stand-alone executable\} programs, \{object\} libraries in
\par \tab\{native\} \{operating system\} formats, \{portable\} \{bytecode\}
\par \tab libraries, \{C\} and \{Lisp\} \{source code\}.
\par 
\par \tab The A# programming language has support for \{object-oriented\}
\par \tab and \{functional programming\} styles.  Both types and functions
\par \tab are \{first class\} values that can be manipulated with a range
\par \tab of flexible and composable \{primitive\}s and user programs.
\par \tab The A# language design places particular emphasis on
\par \tab compilation for efficient \{machine code\} and portability.
\par 
\par \tab Ports have been made to various 16, 32, and 64 bit
\par \tab architectures: \{RS/6000\}, \{SPARC\}, \{DEC Alpha\}, \{i386\},
\par \tab\{i286\}, \{Motorola 680x0\}, \{S 370\}; several \{operating
\par \tab system\}s: \{Linux\}, \{AIX\}, \{SunOS\}, \{HP/UX\}, \{Next\}, \{Mach\} and
\par \tab other \{Unix\} systems, \{OS/2\}, \{DOS\}, \{Microsoft Windows\},
\par \tab\{VMS\} and \{CMS\}; \{C\} compilers: \{Xlc\}, \{gcc\}, \{Sun\},
\par \tab\{Borland\}, \{Metaware\} and \{MIPS\} C.
\par 
\par \tab (1995-02-07)
\par 
\par A-0
\par 
\par \tab <language> (Or A0) A language for the \{UNIVAC I\} or II, using
\par \tab\{three-address code\} instructions for solving mathematical
\par \tab problems.  A-0 was the first language for which a \{compiler\}
\par \tab was developed.  It was produced by \{Grace Hopper\}'s team at
\par \tab\{Remington Rand\} in 1952.  Later internal versions were A-1,
\par \tab A-2, A-3, AT-3.  AT-3 was released as \{MATH-MATIC\}.
\par 
\par \tab ["The A-2 Compiler System", Rem Rand, 1955].
\par 
\par \tab [Sammet 1969, p. 12].
\par 
\par \tab (1995-12-03)
\par 
\par a1
\par 
\par \tab <language> Address 1 code.
\par 
\par \tab An a1 code \{interpreter\}, by Matthew Newhook
\par \tab <matthew@engr.mun.ca> was used to test compiler output.  It
\par \tab requires \{gcc\} 2.4.2 or higher and is portable to computers
\par \tab with \{memory segment\} protection.
\par 
\par \tab\{(ftp://ftp.cs.mun.ca/pub/a1)\}
\par 
\par \tab (1994-07-19)
\par 
\par A1 security
\par 
\par \tab\{Orange Book\}
\par 
\par A20 handler
\par 
\par \tab <software, storage> \{IBM PC\} memory manager software providing
\par \tab\{HMA\}.  \{XMM\}s usually provide this functionality.  Named
\par \tab after the 21st address line (A20), controlling the access to
\par \tab HMA.
\par 
\par \tab (1996-01-10)
\par 
\par A-3
\par 
\par \tab\{ARITH-MATIC\}
\par 
\par A3D
\par 
\par \tab <hardware> (Aureal 3-Dimensional?) A technology developed by
\par \tab\{Aureal\} that delivers sound with a three-dimensional effect
\par \tab through two speakers.  Many modern \{sound cards\} and PC games
\par \tab now support this feature.
\par 
\par \tab A3D differs from the various forms of \{surround sound\} in that
\par \tab it only requires two speakers, while surround sound typically
\par \tab requires four or five.  It is sometimes less convincing than
\par \tab surround sound but is supposedly better in \{interactive\}
\par \tab environments.  For example, PC games in which sounds often
\par \tab move from one speaker to another favour A3D, while
\par \tab pre-recorded video favours surround sound.
\par 
\par \tab\{Home (http://www.a3d.com/)\}.
\par 
\par \tab (1999-01-26)
\par 
\par a56
\par 
\par \tab <language> An \{assembler\} for the \{Motorola\} \{DSP56000\} and
\par \tab\{DSP56001\} \{digital signal processor\}s by Quinn Jensen
\par \tab <jensenq@qcj.icon.com>.  Version 1.1 is available from an
\par \tab\{alt.sources\} archive or \{(ftp://wuarchive.wustl.edu/)\}.
\par 
\par \tab (1992-08-10)
\par 
\par AAC
\par 
\par \tab\{Advanced Audio Coding\}
\par 
\par AADL
\par 
\par \tab\{Axiomatic Architecture Description Language\}
\par 
\par AAL
\par 
\par \tab\{ATM Adaptation Layer\}
\par 
\par AAP
\par 
\par \tab\{Association of American Publishers\}
\par 
\par AAP DTD
\par 
\par \tab <standard> A \{DTD\} for a standard \{SGML\} document type for
\par \tab scientific documents, defined by the \{Association of American
\par \tab Publishers\}.
\par 
\par \tab (1994-11-08)
\par 
\par aard
\par 
\par \tab <programming, tool> (Dutch for "earth") A tool to check memory
\par \tab use for \{C++\} programs, written by Steve Reiss
\par \tab <spr@cs.brown.edu> (who names his programs after living
\par \tab systems).
\par 
\par \tab Aard tracks the state of each byte of memory in the \{heap\} and
\par \tab the \{stack\}.  The state can be one of Undefined,
\par \tab Uninitialised, Free or Set.  The program can detect invalid
\par \tab transitions (i.e. attempting to set or use undefined or free
\par \tab storage or attempting to access uninitialised storage).
\par 
\par \tab In addition, the program keeps track of heap use through
\par \tab\{malloc\} and \{free\} and at the end of the run reports memory
\par \tab blocks that were not freed and that are not accessible
\par \tab (i.e. \{memory leaks\}).
\par 
\par \tab The tools works using a spliced-in \{shared library\} on
\par \tab\{SPARCs\} running \{C++\} 3.0.1 under \{SunOS\} 4.X.
\par 
\par \tab\{(ftp://wilma.cs.brown.edu/pub/aard.tar.Z)\}.
\par 
\par \tab (1998-03-03)
\par 
\par AARP
\par 
\par \tab\{Apple Address Resolution Protocol\}
\par 
\par AARP probe packets
\par 
\par \tab <networking> \{AARP\} \{packets\} sent out on a nonextended
\par \tab\{AppleTalk\} network to discover whether a randomly selected
\par \tab node ID is being used by any node.  If not, the sending node
\par \tab uses the node ID.  If so, it chooses a different ID and sends
\par \tab more AARP probe packets.
\par 
\par \tab (1997-05-03)
\par 
\par AAUI
\par 
\par \tab\{Apple Attachment Unit Interface\}
\par 
\par A&B
\par 
\par \tab <communications> A \{bit signaling procedure\} used in most \{T1\}
\par \tab transmission facilities where one bit from every sixth frame
\par \tab of each of 24 T1 \{subchannels\} is used for carrying
\par \tab\{supervisory signaling\}.
\par 
\par \tab [What does it stand for?  Is this the same as "\{bit
\par \tab robbing\}"?]
\par 
\par \tab (1997-05-05)
\par 
\par abbrev
\par 
\par \tab <jargon> /*-breev'/, /*-brev'/ Common abbreviation for
\par \tab "abbreviation".
\par 
\par \tab (1995-02-27)
\par 
\par Abbreviated Test Language for Avionics Systems
\par 
\par \tab <language> (ATLAS) A Mil-spec language for automatic testing
\par \tab of avionics equipment.  ATLAS replaced \{Gaelic\} and several
\par \tab other test languages.
\par 
\par \tab ["IEEE Standard ATLAS Test Language", IEEE Std 416-1976].
\par 
\par \tab (2000-04-03)
\par 
\par ABC
\par 
\par \tab 1. <language> An \{imperative\} language and programming
\par \tab environment from \{CWI\}, Netherlands.  It is interactive,
\par \tab structured, high-level, and easy to learn and use.  It is a
\par \tab general-purpose language which you might use instead of
\par \tab\{BASIC\}, \{Pascal\} or \{AWK\}.  It is not a systems-programming
\par \tab language but is good for teaching or prototyping.
\par 
\par \tab ABC has only five data types that can easily be combined;
\par \tab\{strong typing\}, yet without declarations; data limited only
\par \tab by memory; refinements to support top-down programming;
\par \tab nesting by indentation.  Programs are typically around a
\par \tab quarter the size of the equivalent \{Pascal\} or \{C\} program,
\par \tab and more readable.
\par 
\par \tab ABC includes a programming environment with \{syntax-directed\}
\par \tab editing, \{suggestion\}s, \{persistent variable\}s and multiple
\par \tab workspaces and \{infinite precision\} arithmetic.
\par 
\par \tab An example function words to collect the set of all words in a
\par \tab document:
\par 
\par \tab    HOW TO RETURN words document:
\par \tab       PUT \{\} IN collection
\par \tab       FOR line in document:
\par \tab          FOR word IN split line:
\par \tab             IF word not.in collection:
\par \tab                INSERT word IN collection
\par \tab       RETURN collection
\par 
\par \tab\{Interpreter\}/\{compiler\}, version 1.04.01, by Leo Geurts,
\par \tab Lambert Meertens, Steven Pemberton <Steven.Pemberton@cwi.nl>.
\par \tab ABC has been ported to \{Unix\}, \{MS-DOS\}, \{Atari\}, \{Macintosh\}.
\par 
\par \tab\{Home (http://www.cwi.nl/cwi/projects/abc.html)\}
\par 
\par \tab\{FTP eu.net (ftp://ftp.eu.net/programming/languages/abc)\},
\par \tab\{FTP nluug.nl (ftp://ftp.nluug.nl/programming/languages/abc)\},
\par \tab\{FTP uunet (ftp://ftp.uu.net/languages/abc)\}.
\par 
\par \tab Mailing list: <abc-list-request@cwi.nl>.
\par 
\par \tab E-mail: <abc@cwi.nl>.
\par 
\par \tab ["The ABC Programmer's Handbook" by Leo Geurts, Lambert
\par \tab Meertens and Steven Pemberton, published by Prentice-Hall
\par \tab (ISBN 0-13-000027-2)].
\par 
\par \tab ["An Alternative Simple Language and Environment for PCs" by
\par \tab Steven Pemberton, IEEE Software, Vol. 4, No. 1, January 1987,
\par \tab pp. 56-64.]
\par 
\par \tab (1995-02-09)
\par 
\par \tab 2. <language> Argument, Basic value, C?.
\par 
\par \tab An \{abstract machine\} for implementation of \{functional
\par \tab language\}s and its intermediate code.
\par 
\par \tab [P. Koopman, "Functional Programs as Executable
\par \tab Specifications", 1990].
\par 
\par \tab (1995-02-09)
\par 
\par ABC ALGOL
\par 
\par \tab <language> An extension of \{ALGOL 60\} with arbitrary data
\par \tab structures and user-defined operators, for \{symbolic
\par \tab mathematics\}.
\par 
\par \tab ["ABC ALGOL, A Portable Language for Formula Manipulation
\par \tab Systems", R.P. van de Riet, Amsterdam Math Centrum 1973].
\par 
\par \tab (1994-10-28)
\par 
\par ABCL/1
\par 
\par \tab <language> An Object-Based Concurrent Language.
\par 
\par \tab The language for the \{ABCL\} \{MIMD\} system, written by Akinori
\par \tab Yonezawa <matsu@is.s.u-tokyo.ac.jp> of Department of
\par \tab Information Science, \{Tokyo University\} in 1986.  ABCL/1 uses
\par \tab\{asynchronous\} \{message passing\} to \{object\}s.  It requires
\par \tab\{Common Lisp\}.  Implementations in \{KCL\} and \{Symbolics Lisp\}
\par \tab are available from the author.
\par 
\par \tab\{(ftp://camille.is.s.u-tokyo.ac.jp/)\}
\par 
\par \tab E-mail: <abcl@is.s.u-tokyo.ac.jp>.
\par 
\par \tab ["ABCL: An Object-Oriented Concurrent System", A. Yonezawa ed,
\par \tab MIT Press 1990].  (1990-05-23).
\par 
\par \tab (1995-02-09)
\par 
\par ABCL/c+
\par 
\par \tab <language> A \{concurrent\} \{object-oriented\} language, an
\par \tab extension of \{ABCL/1\} based on \{C\}.
\par 
\par \tab ["An Implementation of An Operating System Kernel using
\par \tab Concurrent Object Oriented Language ABCL/c+", N. Doi et al in
\par \tab ECOOP '88, S. Gjessing et al eds, LNCS 322, Springer 1988].
\par 
\par \tab (1994-11-08)
\par 
\par ABCL/R
\par 
\par \tab <language> A \{reflective\} subset of \{ABCL/1\}, written in
\par \tab ABCL/1 by Yonezawa of \{Tokyo Institute of Technology\} in 1988.
\par 
\par \tab\{(ftp://camille.is.s.u-tokyo.ac.jp/pub/abclr)\}
\par 
\par \tab ["Reflection in an Object-Oriented Concurrent Language",
\par \tab T. Watanabe et al, SIGPLAN Notices 23(11):306-315 (Nov 1988)].
\par 
\par \tab (1994-11-08)
\par 
\par ABCL/R2
\par 
\par \tab <language> An \{object-oriented\}, \{concurrent\}, \{reflective\}
\par \tab language based on \{Hybrid Group Architecture\}. ABCL/R2 was
\par \tab produced by <masuhara@is.s.u-tokyo.ac.jp>,
\par \tab <matsu@is.s.u-tokyo.ac.jp>, <takuo@is.s.u-tokyo.ac.jp>,
\par \tab <yonezawa@is.s.u-tokyo.ac.jp>, at the \{Tokyo Institute of
\par \tab Technology\} in 1992.
\par 
\par \tab As a reflective language, an ABCL/R2 program can dynamically
\par \tab control its own behaviour, such as \{scheduling\} policy, from
\par \tab within a user-program.  This system has almost all functions
\par \tab of \{ABCL/1\} and is written in \{Common Lisp\}.
\par 
\par \tab\{(ftp://camille.is.s.u-tokyo.ac.jp/pub/abclr2/)\}
\par 
\par \tab (1993-01-28)
\par 
\par abduction
\par 
\par \tab <logic> The process of \{inference\} to the best explanation.
\par 
\par \tab "Abduction" is sometimes used to mean just the generation of
\par \tab hypotheses to explain observations or conclusionsm, but the
\par \tab former definition is more common both in philosophy and
\par \tab computing.
\par 
\par \tab The \{semantics\} and the implementation of abduction cannot be
\par \tab reduced to those for \{deduction\}, as explanation cannot be
\par \tab reduced to implication.
\par 
\par \tab Applications include fault diagnosis, plan formation and
\par \tab\{default reasoning\}.
\par 
\par \tab\{Negation as failure\} in \{logic programming\} can both be given
\par \tab an abductive interpretation and also can be used to implement
\par \tab abduction.  The abductive semantics of negation as failure
\par \tab leads naturally to an \{argumentation\}-theoretic interpretation
\par \tab of default reasoning in general.
\par 
\par \tab [Better explanation?  Example?]
\par 
\par \tab ["Abductive Inference", John R. Josephson
\par \tab <jj@cis.ohio-state.edu>].
\par 
\par \tab (2000-12-07)
\par 
\par ABEND
\par 
\par \tab <jargon> /o'bend/, /*-bend'/ ABnormal END.  Abnormal
\par \tab termination (of \{software\}); \{crash\}; \{lossage\}.  Derives from
\par \tab an error message on the \{IBM 360\}; used jokingly by hackers
\par \tab but seriously mainly by \{code grinder\}s.  Usually capitalised,
\par \tab but may appear as "abend".  Hackers will try to persuade you
\par \tab that ABEND is called "abend" because it is what system
\par \tab operators do to the computer late on Friday when they want to
\par \tab call it a day, and hence is from the German "Abend" =
\par \tab "Evening".
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (1994-11-08)
\par 
\par ABI
\par 
\par \tab\{Application Binary Interface\}
\par 
\par ABLE
\par 
\par \tab <language> A simple language for accountants.
\par 
\par \tab ["ABLE, The Accounting Language, Programming and Reference
\par \tab Manual," Evansville Data Proc Center, Evansville, IN, Mar
\par \tab 1975].
\par 
\par \tab [Listed in SIGPLAN Notices 13(11):56 (Nov 1978)].
\par 
\par \tab (1994-11-08)
\par 
\par ABM
\par 
\par \tab\{Asynchronous Balanced Mode\}
\par 
\par ABNF
\par 
\par \tab\{Augmented Backus-Naur Form\}
\par 
\par abort
\par 
\par \tab <programming> To terminate a program or \{process\} abnormally
\par \tab and usually suddenly, with or without \{diagnostic\}
\par \tab information.  "My program aborted", "I aborted the
\par \tab transmission".  The noun form in computing is "abort", not
\par \tab "abortion", e.g. "We've had three aborts over the last two
\par \tab days".
\par 
\par \tab If a \{Unix\} \{kernel\} aborts it is known as a \{panic\}.
\par 
\par \tab (1997-01-07)
\par 
\par ABP
\par 
\par \tab 1. <networking> \{Alternating bit protocol\}.
\par 
\par \tab 2. \{Microsoft\} \{Address Book Provider\}.
\par 
\par \tab (2001-02-11)
\par 
\par ABR
\par 
\par \tab\{automatic baud rate detection\}
\par 
\par abscissa
\par 
\par \tab <mathematics> The x coordinate on an (x, y) graph; the input of
\par \tab a function against which the output is plotted.
\par 
\par \tab y is the "\{ordinate\}".
\par 
\par \tab See \{Cartesian coordinates\}.
\par 
\par \tab (1997-07-08)
\par 
\par ABSET
\par 
\par \tab <language> An early \{declarative language\} from the
\par \tab\{University of Aberdeen\}.
\par 
\par \tab ["ABSET: A Programming Language Based on Sets", E.W. Elcock et
\par \tab al, Mach Intell 4, Edinburgh U Press, 1969, pp.467-492].
\par 
\par \tab (1994-11-08)
\par 
\par absolute path
\par 
\par \tab <file system> A \{path\} relative to the \{root directory\}.  Its
\par \tab first character must be the \{pathname separator\}.
\par 
\par \tab (1996-11-21)
\par 
\par absolute pathname
\par 
\par \tab <file system> A \{pathname\} relative to the \{root directory\}.
\par 
\par \tab (1996-11-21)
\par 
\par abstract class
\par 
\par \tab <programming> In \{object-oriented programming\}, a \{class\}
\par \tab designed only as a parent from which sub-classes may be
\par \tab derived, but which is not itself suitable for instantiation.
\par \tab Often used to "abstract out" incomplete sets of features which
\par \tab may then be shared by a group of sibling sub-classes which add
\par \tab different variations of the missing pieces.
\par 
\par \tab (1994-11-08)
\par 
\par abstract data type
\par 
\par \tab <programming> (ADT) A type whose internal form is hidden
\par \tab behind a set of \{access function\}s.  Objects of the type are
\par \tab created and inspected only by calls to the access functions.
\par \tab This allows the implementation of the type to be changed
\par \tab without requiring any changes outside the \{module\} in which it
\par \tab is defined.
\par 
\par \tab Abstract data types are central to \{object-oriented
\par \tab programming\} where every \{class\} is an ADT.
\par 
\par \tab A classic example of an ADT is a \{stack\} data type for which
\par \tab functions might be provided to create an empty stack, to
\par \tab\{push\} values onto a stack and to \{pop\} values from a stack.
\par 
\par \tab (1995-02-22)
\par 
\par abstract interpretation
\par 
\par \tab <theory> A partial execution of a program which gains
\par \tab information about its \{semantics\} (e.g. control structure,
\par \tab flow of information) without performing all the calculations.
\par \tab Abstract interpretation is typically used by compilers to
\par \tab analyse programs in order to decide whether certain
\par \tab optimisations or transformations are applicable.
\par 
\par \tab The objects manipulated by the program (typically values and
\par \tab functions) are represented by points in some \{domain\}.  Each
\par \tab abstract domain point represents some set of real
\par \tab ("\{concrete\}") values.
\par 
\par \tab For example, we may take the abstract points "+", "0" and "-"
\par \tab to represent positive, zero and negative numbers and then
\par \tab define an abstract version of the multiplication operator, *#,
\par \tab which operates on abstract values:
\par 
\par \tab\tab *# | + 0 -
\par \tab\tab ---|------
\par \tab\tab +  | + 0 -
\par \tab\tab 0  | 0 0 0
\par \tab\tab -  | - 0 +
\par 
\par \tab An interpretation is "safe" if the result of the abstract
\par \tab operation is a safe approximation to the abstraction of the
\par \tab concrete result.  The meaning of "a safe approximation"
\par \tab depends on how we are using the results of the analysis.
\par 
\par \tab If, in our example, we assume that smaller values are safer
\par \tab then the "safety condition" for our interpretation (#) is
\par 
\par \tab\tab a# *# b# <= (a * b)#
\par 
\par \tab where a# is the abstract version of a etc.
\par 
\par \tab In general an interpretation is characterised by the \{domain\}s
\par \tab used to represent the basic types and the abstract values it
\par \tab assigns to constants (where the constants of a language
\par \tab include primitive functions such as *).  The interpretation of
\par \tab constructed types (such as user defined functions, \{sum type\}s
\par \tab and \{product type\}s) and expressions can be derived
\par \tab systematically from these basic domains and values.
\par 
\par \tab A common use of \{abstract interpretation\} is \{strictness
\par \tab analysis\}.
\par 
\par \tab See also \{standard interpretation\}.
\par 
\par \tab (1994-11-08)
\par 
\par abstraction
\par 
\par \tab 1. Generalisation; ignoring or hiding details to capture some
\par \tab kind of commonality between different instances.  Examples are
\par \tab\{abstract data types\} (the representation details are hidden),
\par \tab\{abstract syntax\} (the details of the \{concrete syntax\} are
\par \tab ignored), \{abstract interpretation\} (details are ignored to
\par \tab analyse specific properties).
\par 
\par \tab 2. <programming> Parameterisation, making something a function
\par \tab of something else.  Examples are \{lambda abstractions\} (making
\par \tab a term into a function of some variable), \{higher-order
\par \tab function\}s (parameters are functions), \{bracket abstraction\}
\par \tab (making a term into a function of a variable).
\par 
\par \tab Opposite of \{concretisation\}.
\par 
\par \tab (1998-06-04)
\par 
\par abstract machine
\par 
\par \tab 1. <language> A processor design which is not intended to be
\par \tab implemented as \{hardware\}, but which is the notional executor
\par \tab of a particular \{intermediate language\} (abstract machine
\par \tab language) used in a \{compiler\} or \{interpreter\}.  An abstract
\par \tab machine has an \{instruction set\}, a \{register set\} and a model
\par \tab of memory.  It may provide instructions which are closer to
\par \tab the language being compiled than any physical computer or it
\par \tab may be used to make the language implementation easier to
\par \tab\{port\} to other \{platform\}s.
\par 
\par \tab A \{virtual machine\} is an abstract machine for which an
\par \tab\{interpreter\} exists.
\par 
\par \tab Examples: \{ABC\}, \{Abstract Machine Notation\}, \{ALF\}, \{CAML\},
\par \tab\{F-code\}, \{FP/M\}, \{Hermes\}, \{LOWL\},
\par \tab\{Christmas\}, \{SDL\}, \{S-K reduction machine\}, \{SECD\}, \{Tbl\},
\par \tab\{Tcode\}, \{TL0\}, \{WAM\}.
\par 
\par \tab 2. <theory> A procedure for executing a set of instructions in
\par \tab some formal language, possibly also taking in input data and
\par \tab producing output.  Such abstract machines are not intended to
\par \tab be constructed as \{hardware\} but are used in thought
\par \tab experiments about \{computability\}.
\par 
\par \tab Examples: \{Finite State Machine\}, \{Turing Machine\}.
\par 
\par \tab (1995-03-13)
\par 
\par Abstract Machine Notation
\par 
\par \tab <language> (AMN) A language for specifying \{abstract machines\}
\par \tab in the \{B-Method\}, based on the mathematical theory of
\par \tab\{Generalised Substitutions\}.
\par 
\par \tab (1995-03-13)
\par 
\par abstract syntax
\par 
\par \tab <language, data> A representation of data (typically either a
\par \tab message passing over a communications link or a program being
\par \tab compiled) which is independent of machine-oriented structures
\par \tab and encodings and also of the physical representation of the
\par \tab data (called "\{concrete syntax\}" in the case of compilation or
\par \tab "\{transfer syntax\}" in communications).
\par 
\par \tab A \{compiler\}'s internal representation of a program will
\par \tab typically be specified by an abstract syntax in terms of
\par \tab categories such as "statement", "expression" and "identifier".
\par \tab This is independent of the source syntax (\{concrete syntax\})
\par \tab of the language being compiled (though it will often be very
\par \tab similar).  A \{parse tree\} is similar to an abstract syntax
\par \tab tree but it will typically also contain features such as
\par \tab parentheses which are syntactically significant but which are
\par \tab implicit in the structure of the \{abstract syntax tree\}.
\par 
\par \tab (1998-05-26)
\par 
\par Abstract Syntax Notation 1
\par 
\par \tab <language, standard, protocol> (ASN.1, X.208, X.680) An
\par \tab\{ISO\}/\{ITU-T\} \{standard\} for transmitting structured \{data\} on
\par \tab\{networks\}, originally defined in 1984 as part of \{CCITT
\par \tab X.409\} '84.  ASN.1 moved to its own standard, X.208, in 1998
\par \tab due to wide applicability.  The substantially revised 1995
\par \tab version is covered by the X.680 series.
\par 
\par \tab ASN.1 defines the \{abstract syntax\} of \{information\} but does
\par \tab not restrict the way the information is encoded.  Various
\par \tab ASN.1 encoding rules provide the \{transfer syntax\} (a
\par \tab\{concrete\} representation) of the data values whose \{abstract
\par \tab syntax\} is described in ASN.1.  The standard ASN.1 encoding
\par \tab rules include \{BER\} (Basic Encoding Rules - X.209), \{CER\}
\par \tab (Canonical Encoding Rules), \{DER\} (Distinguished Encoding
\par \tab Rules), and \{PER\} (Packed Encoding Rules).
\par 
\par \tab ASN.1 together with specific ASN.1 encoding rules facilitates
\par \tab the exchange of structured data especially between
\par \tab\{application programs\} over networks by describing data
\par \tab structures in a way that is independent of machine
\par \tab architecture and implementation language.
\par 
\par \tab\{OSI\} \{Application layer\} \{protocols\} such as \{X.400\} \{MHS\}
\par \tab\{electronic mail\}, \{X.500\} directory services and \{SNMP\} use
\par \tab ASN.1 to describe the \{PDU\}s they exchange.
\par 
\par \tab Documents describing the ASN.1 notations: \{ITU-T\} Rec. X.680,
\par \tab\{ISO\} 8824-1; \{ITU-T\} Rec. X.681, \{ISO\} 8824-2; \{ITU-T\}
\par \tab Rec. X.682, \{ISO\} 8824-3; \{ITU-T\} Rec. X.683, \{ISO\} 8824-4
\par 
\par \tab Documents describing the ASN.1 encoding rules: \{ITU-T\}
\par \tab Rec. X.690, \{ISO\} 8825-1; \{ITU-T\} Rec. X.691, \{ISO\} 8825-2.
\par 
\par \tab [M. Sample et al, "Implementing Efficient Encoders and
\par \tab Decoders for Network Data Representations", IEEE Infocom 93
\par \tab Proc, v.3, pp. 1143-1153, Mar 1993.  Available from Logica,
\par \tab UK].
\par 
\par \tab See also \{snacc\}.
\par 
\par \tab (2000-10-20)
\par 
\par abstract syntax tree
\par 
\par \tab <compiler> (AST) A data structure representing something which
\par \tab has been parsed, often used as a \{compiler\} or \{interpreter\}'s
\par \tab internal representation of a program while it is being
\par \tab optimised and from which \{code generation\} is performed.  The
\par \tab range of all possible such structures is described by the
\par \tab\{abstract syntax\}.
\par 
\par \tab (1994-11-08)
\par 
\par Abstract-Type and Scheme-Definition Language
\par 
\par \tab <language> (ASDL) A language developed as part of \{Esprit\}
\par \tab project \{GRASPIN\}, as a basis for generating \{language-based
\par \tab editor\}s and environments.  It combines an \{object-oriented\}
\par \tab type system, syntax-directed translation schemes and a
\par \tab target-language interface.
\par 
\par \tab ["ASDL - An Object-Oriented Specification Language for
\par \tab Syntax-Directed Environments", M.L. Christ-Neumann et al,
\par \tab European Software Eng Conf, Strasbourg, Sept 1987, pp.77-85].
\par 
\par \tab (1996-02-19)
\par 
\par Abstract Windowing Toolkit
\par 
\par \tab\{Abstract Window Toolkit\}
\par 
\par Abstract Window Toolkit
\par 
\par \tab <graphics> (AWT) \{Java\}'s \{platform\}-independent \{windowing\},
\par \tab graphics, and user-interface \{toolkit\}.  The AWT is part of
\par \tab the \{Java Foundation Classes\} (JFC) - the standard \{API\} for
\par \tab providing a \{graphical user interface\} (GUI) for a Java
\par \tab program.
\par 
\par \tab Compare: \{SWING\}.
\par 
\par \tab ["Java in a Nutshell", O'Reilly].
\par 
\par \tab\{Home (http://java.sun.com/products/jdk/awt/)\}.
\par 
\par \tab (2000-07-26)
\par 
\par ABSYS
\par 
\par \tab <language> An early \{declarative language\} from the
\par \tab\{University of Aberdeen\} which anticipated a number of
\par \tab features of Prolog.
\par 
\par \tab ["ABSYS: An Incremental Compiler for Assertions", J.M. Foster
\par \tab et al, Mach Intell 4, Edinburgh U Press, 1969, pp. 423-429].
\par 
\par \tab (1994-11-08)
\par 
\par AC2
\par 
\par \tab <audio> An \{audio\} format, succeded by \{AC3\}.
\par 
\par \tab (2001-12-18)
\par \tab\tab 
\par AC3
\par 
\par \tab <audio> An \{audio\} format by Sony[?], the successor of \{AC2\}.
\par \tab AC3 is used for multi-channel \{audio\} for \{digital video\}.
\par 
\par \tab (2001-12-18)
\par 
\par ACA
\par 
\par \tab\{Application Control Architecture\}
\par 
\par ACAP
\par 
\par \tab\{Application Configuration Access Protocol\}
\par 
\par Accelerated Graphics Port
\par 
\par \tab <hardware> (AGP) A bus specification by \{Intel\} which gives
\par \tab low-cost 3D \{graphics cards\} faster access to \{main memory\} on
\par \tab\{personal computers\} than the usual PCI bus.
\par 
\par \tab AGP dynamically allocates the PC's normal RAM to store the
\par \tab screen image and to support \{texture mapping\}, \{z-buffering\}
\par \tab and \{alpha blending\}.
\par 
\par \tab Intel has built AGP into a \{chipset\} for its \{Pentium II\}
\par \tab microprocessor.  AGP cards are slightly longer than a PCI
\par \tab card.
\par 
\par \tab AGP operates at 66 \{MHz\}, doubled to 133 MHz, compared with
\par \tab PCI's 33 Mhz.  AGP allows for efficient use of \{frame buffer\}
\par \tab memory, thereby helping 2D graphics performance as well.
\par 
\par \tab AGP provides a coherent memory management design which allows
\par \tab scattered data in system memory to be read in rapid bursts.
\par \tab AGP reduces the overall cost of creating high-end graphics
\par \tab subsystems by using existing system memory.
\par 
\par \tab\{AGP Implementors Forum AGP FAQ
\par \tab (http://www.agpforum.org/faq_ans.htm)\}.
\par 
\par \tab\{Specification
\par \tab (http://developer.intel.com/pc-supp/platform/agfxport/)\}.
\par 
\par \tab\{Intel AGP news
\par \tab (http://developer.intel.com/solutions/tech/agp.htm)\}.
\par 
\par \tab (1999-01-08)
\par 
\par accelerator
\par 
\par \tab <hardware> Additional hardware to perform some function faster
\par \tab than is possible in software running on the normal \{CPU\}.
\par \tab Examples include \{graphics accelerator\}s and \{floating-point
\par \tab accelerator\}s.
\par 
\par \tab (1994-11-08)
\par 
\par Accent
\par 
\par \tab <language> A very high level interpreted language from
\par \tab\{CaseWare, Inc.\} with strings and tables.  It is \{strongly
\par \tab typed\} and has remote function calls.
\par 
\par \tab (1994-11-08)
\par 
\par accept
\par 
\par \tab <library, networking> \{Berkeley\} \{Unix\} networking \{socket\}
\par \tab library routine to satisfy a connection request from a remote
\par \tab\{host\}.  A specified socket on the local host (which must be
\par \tab capable of accepting the connection) is connected to the
\par \tab requesting socket on the remote host.  The remote socket's
\par \tab socket address is returned.
\par 
\par \tab\{Unix manual pages\}: accept(2), connect(2).
\par 
\par \tab (1994-11-08)
\par 
\par Acceptable Use Policy
\par 
\par \tab <networking> (AUP) Rules applied by many \{transit network\}s
\par \tab which restrict the use to which the network may be put.  A
\par \tab well known example is \{NSFNet\} which does not allow commercial
\par \tab use.  Enforcement of AUPs varies with the network.
\par 
\par \tab (1994-11-08)
\par 
\par acceptance testing
\par 
\par \tab <programming> Formal testing conducted to determine whether a
\par \tab system satisfies its acceptance criteria and thus whether the
\par \tab customer should accept the system.
\par 
\par \tab (1996-05-10)
\par 
\par Acceptance, Test Or Launch Language
\par 
\par \tab <language> (ATOLL) The language used for automating the
\par \tab checking and launch of Saturn rockets.
\par 
\par \tab ["SLCC ATOLL User's Manual", IBM 70-F11-0001, Huntsville AL
\par \tab Dec 1970].
\par 
\par \tab (2000-04-03)
\par 
\par acceptor
\par 
\par \tab\{Finite State Machine\}
\par 
\par Access
\par 
\par \tab 1. <language> An English-like query language used in the
\par \tab\{Pick\} \{operating system\}.
\par 
\par \tab 2. <database, product> \{Microsoft Access\}.
\par 
\par \tab (1994-11-08)
\par 
\par Access Control List
\par 
\par \tab <networking> (ACL) A list of the services available on a
\par \tab\{server\}, each with a list of the \{host\}s permitted to use the
\par \tab service.
\par 
\par \tab (1994-11-08)
\par 
\par access method
\par 
\par \tab <networking> 1. The way that network devices access the
\par \tab network medium.
\par 
\par \tab 2. Software in an \{SNA\} processor that controls the flow of
\par \tab data through a \{network\}.
\par 
\par \tab [\{physical layer\}?]
\par 
\par \tab (1998-03-02)
\par 
\par access permission
\par 
\par \tab\{permission\}
\par 
\par access time
\par 
\par \tab <hardware, storage> The average time interval between a
\par \tab storage peripheral (usually a \{disk drive\} or \{semiconductor\}
\par \tab memory) receiving a request to read or write a certain
\par \tab location and returning the value read or completing the write.
\par 
\par \tab (1997-06-14)
\par 
\par ACCLAIM
\par 
\par \tab <project> A European Union \{ESPRIT\} \{Basic Research Action\}.
\par 
\par \tab [What's it about?]
\par 
\par \tab (1994-11-08)
\par 
\par Accounting File
\par 
\par \tab <operating system> A file which holds records of the resources
\par \tab used by individual jobs.  These records are used to regulate,
\par \tab and calculate charges for, resources.  An entry is opened in
\par \tab the accounting file as each job begins.
\par 
\par \tab (1996-12-08)
\par 
\par accounting management
\par 
\par \tab <networking> The process of identifying individual and group
\par \tab access to various network resources to ensure proper access
\par \tab capabilities (\{bandwidth\} and security) or to properly charge
\par \tab the various individuals and departments.  Accounting
\par \tab management is one of five categories of \{network management\}
\par \tab defined by \{ISO\} for management of \{OSI\} \{networks\}.
\par 
\par \tab (1997-05-05)
\par 
\par ACCU
\par 
\par \tab\{Association of C and C++ Users\}
\par 
\par accumulator
\par 
\par \tab <processor> In a \{central processing unit\}, a \{register\} in
\par \tab which intermediate results are stored.  Without an
\par \tab accumulator, it would be necessary to write the result of each
\par \tab calculation (addition, multiplication, \{shift\}, etc.) to \{main
\par \tab memory\} and read them back.  Access to main memory is slower
\par \tab than access to the accumulator which usually has direct paths
\par \tab to and from the \{arithmetic and logic unit\} (ALU).
\par 
\par \tab The \{canonical\} example is summing a list of numbers.  The
\par \tab accumulator is set to zero initially, each number in turn is
\par \tab added to the value in the accumulator and only when all
\par \tab numbers have been added is the result written to main memory.
\par 
\par \tab Modern CPUs usually have many registers, all or many of which
\par \tab can be used as accumulators.  For this reason, the term
\par \tab "accumulator" is somewhat archaic.  Use of it as a synonym for
\par \tab "register" is a fairly reliable indication that the user has
\par \tab been around for quite a while and/or that the architecture
\par \tab under discussion is quite old.  The term in full is almost
\par \tab never used of microprocessor registers, for example, though
\par \tab symbolic names for arithmetic registers beginning in "A"
\par \tab derive from historical use of the term "accumulator" (and not,
\par \tab actually, from "arithmetic").  Confusingly, though, an "A"
\par \tab register name prefix may also stand for "address", as for
\par \tab example on the \{Motorola\} \{680x0\} family.
\par 
\par \tab 2. <programming> A register, memory location or variable being
\par \tab used for arithmetic or logic (as opposed to addressing or a
\par \tab loop index), especially one being used to accumulate a sum or
\par \tab count of many items.  This use is in context of a particular
\par \tab routine or stretch of code.  "The FOOBAZ routine uses A3 as an
\par \tab accumulator."
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (1999-04-20)
\par 
\par accuracy
\par 
\par \tab <mathematics> How close to the real value a measurement is.
\par 
\par \tab Compare \{precision\}.
\par 
\par \tab (1998-04-19)
\par 
\par ACE
\par 
\par \tab 1. \{Advanced Computing Environment\}.
\par 
\par \tab 2. \{Adaptive Communication Environment\}.
\par 
\par ACF
\par 
\par \tab\{Advanced Communications Function\}
\par 
\par ACF/NCP
\par 
\par \tab\{Advanced Communication Function/Network Control Program\}
\par 
\par ACIA
\par 
\par \tab\{Asynchronous Communications Interface Adapter\}
\par 
\par ACID
\par 
\par \tab <programming> A \{mnemonic\} for the properties a transaction
\par \tab should have to satisfy the \{Object Management Group\}
\par \tab\{Transaction Service\} specifications.  A transaction should be
\par \tab\{Atomic\}, its result should be Consistent, Isolated
\par \tab (independent of other transactions) and Durable (its effect
\par \tab should be permanent).
\par 
\par \tab The \{Transaction Service\} specifications which part of the
\par \tab\{Object Services\}, an adjunct to the \{CORBA\} specifications.
\par 
\par \tab (1997-05-15)
\par 
\par ACIS
\par 
\par \tab <graphics> Andy, Charles, Ian's System.
\par 
\par \tab A \{geometric engine\} that most \{CAD\} packages now use.  ACIS
\par \tab uses a sophisticated \{object-oriented\} approach for modelling,
\par \tab the data is stored in \{boundary representation\}.  Acis is
\par \tab owned by \{Spatial Technologies\}.
\par 
\par \tab [How does this differ from "solid modelling"?].
\par 
\par \tab (1996-03-21)
\par 
\par ACK
\par 
\par \tab 1. <character> /ak/ The \{mnemonic\} for the ACKnowledge
\par \tab character, \{ASCII\} code 6.
\par 
\par \tab 2. <communications> A message transmitted to indicate that
\par \tab some data has been received correctly.  Typically, if the
\par \tab sender does not receive the ACK message after some
\par \tab predetermined time, or receives a \{NAK\}, the original data
\par \tab will be sent again.
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (1997-01-07)
\par 
\par ACL
\par 
\par \tab 1. \{Access Control List\}.
\par 
\par \tab 2. \{Association for Computational Linguistics\}.
\par 
\par \tab 3. A Coroutine Language.
\par 
\par \tab A \{Pascal\}-based implementation of \{coroutine\}s.
\par 
\par \tab ["Coroutines", C.D. Marlin, LNCS 95, Springer 1980].
\par 
\par \tab (1994-11-08)
\par 
\par ACM
\par 
\par \tab 1. <body> The \{Association for Computing\}.
\par 
\par \tab 2. <communications> \{addressed call mode\}.
\par 
\par \tab (1997-05-07)
\par 
\par ACME
\par 
\par \tab <company, jargon> /ak'mee/ 1. A Company that Makes Everything.
\par \tab The \{canonical\} imaginary business.  Possibly also derived
\par \tab from the word "acme" meaning "highest point".
\par 
\par \tab 2. A program for \{MS-DOS\}.
\par 
\par \tab [What does it do?]
\par 
\par \tab (1994-11-08)
\par 
\par ACOM
\par 
\par \tab <language> An early system on the \{IBM 705\}.
\par 
\par \tab [Listed in CACM 2(5):16 (May 1959)].
\par 
\par \tab (1994-11-08)
\par 
\par Acorn Archimedes
\par 
\par \tab\{Archimedes\}
\par 
\par Acorn Computer Group
\par 
\par \tab <company> A holding company for \{Acorn Computers\} Limited,
\par \tab Acorn Australia, Acorn New Zealand, Acorn GmbH and \{Online
\par \tab Media\}.  Acorn Computer Group owns 43% of \{Advanced RISC
\par \tab Machines\} Ltd.
\par 
\par \tab (1994-11-08)
\par 
\par Acorn Computers Ltd.
\par 
\par \tab <company> A UK computer manufacturer, part of the \{Acorn
\par \tab Computer Group\} plc.  Acorn was founded on 1978-12-05, on a
\par \tab kitchen table in a back room.  Their first creation was an
\par \tab electronic slot machine.  After the \{Acorn System 1\}, 2 and 3,
\par \tab Acorn launched the first commercial \{microcomputer\} - the
\par \tab\{ATOM\} in March 1980.  In April 1981, Acorn won a contract
\par \tab from the \{BBC\} to provide the \{PROTON\}.  In January 1982 Acorn
\par \tab launched the \{BBC Microcomputer\} System.  At one time, 70% of
\par \tab microcomputers bought for UK schools were BBC Micros.
\par 
\par \tab The Acorn Computer Group went public on the Unlisted
\par \tab Securities Market in September 1983.  In April 1984 Acorn won
\par \tab the Queen's Award for Technology for the BBC Micro and in
\par \tab September 1985 \{Olivetti\} took a controlling interest in
\par \tab Acorn.  The \{Master\} 128 Series computers were launched in
\par \tab January 1986 and the BBC \{Domesday\} System in November 1986.
\par 
\par \tab In 1983 Acorn began to design the Acorn RISC Machine (ARM),
\par \tab the first low-cost, high volume \{RISC\} processor chip (later
\par \tab renamed the \{Advanced RISC Machine\}).  In June 1987 they
\par \tab launched the \{Archimedes\} range - the first 32-bit \{RISC\}
\par \tab based \{microcomputers\} - which sold for under UKP 1000.  In
\par \tab February 1989 the R140 was launched.  This was the first
\par \tab\{Unix\} \{workstation\} under UKP 4000.  In May 1989 the A3000
\par \tab (the new \{BBC Microcomputer\}) was launched.
\par 
\par \tab In 1990 Acorn formed \{Advanced RISC Machines\} Ltd. (ARM) in
\par \tab partnership with \{Apple Computer, Inc.\} and \{VLSI\} to develop
\par \tab the ARM processor.  Acorn has continued to develop \{RISC\}
\par \tab based products.
\par 
\par \tab With 1992 revenues of 48.2 million pounds, Acorn Computers was
\par \tab the premier supplier of \{Information Technology\} products to
\par \tab UK education and had been the leading provider of 32-bit RISC
\par \tab based \{personal computers\} since 1987.
\par 
\par \tab Acorn finally folded in the late 1990s.  Their operating
\par \tab system, \{RISC OS\} was further developed by a consortium of
\par \tab suppliers.
\par 
\par \tab\{Usenet\} newsgroups: \{news:comp.sys.acorn\},
\par \tab\{news:comp.sys.acorn.announce\}, \{news:comp.sys.acorn.tech\},
\par \tab\{news:comp.binaries.acorn\}, \{news:comp.sources.acorn\},
\par \tab\{news:comp.sys.acorn.advocacy\}, \{news:comp.sys.acorn.games\}.
\par 
\par \tab\{Acorn's FTP server (ftp://ftp.acorn.co.uk/)\}
\par 
\par \tab\{HENSA software archive
\par \tab (http://micros.hensa.ac.uk/micros/arch.html)\}.  \{Richard
\par \tab Birkby's Acorn page (http://www.csv.warwick.ac.uk/~phudv/)\}.
\par \tab\{RiscMan's Acorn page (http://www.geko.com.au/riscman/)\}.
\par \tab\{Acorn On The Net (http://www.stir.ac.uk/~rhh01/Main.html)\}.
\par \tab\{"The Jungle" by Simon Truss
\par \tab (http://www.csc.liv.ac.uk/users/u1smt/u1smt.html)\}.
\par 
\par \tab [Recent history?]
\par 
\par \tab (2000-09-26)
\par 
\par Acorn RISC Machine
\par 
\par \tab <processor> The original name of the \{Advanced RISC Machine\}.
\par 
\par \tab (1995-03-07)
\par 
\par ACOS
\par 
\par \tab <language> A \{BBS\} language for \{PRODOS 8\} on \{Apple II\}.
\par \tab\{Macos\} is a hacked version of ACOS.
\par 
\par \tab (1994-11-08)
\par 
\par acoustic coupler
\par 
\par \tab <hardware, communications> A device used to connect a \{modem\}
\par \tab to a telephone line via an ordinary handset.  The acoustic
\par \tab coupler converts electrical signals from the \{modem\} to sound
\par \tab via a loudspeaker, against which the mouthpiece of a telephone
\par \tab handset is placed.  The earpiece is placed against a
\par \tab microphone which converts sound to electrical signals which
\par \tab return to the modem.  The handset is inserted into a
\par \tab sound-proof box containing the louspeaker and microphone to
\par \tab avoid interference from ambient noise.
\par 
\par \tab Acousitic couplers are now rarely used since most modems have
\par \tab a direct electrical connection to the telephone line.  This
\par \tab avoids the signal degradation caused by conversion to and from
\par \tab audio.  Direct connection is not always possible, and was
\par \tab actually illegal in the United Kingdom before \{British
\par \tab Telecom\} was privatised.  BT's predecessor, the General Post
\par \tab Office, did not allow subscribers to connect their own
\par \tab equipment to the telephone line.
\par 
\par \tab (1994-11-08)
\par 
\par ACP
\par 
\par \tab\{Algebra of Communicating Processes\}
\par 
\par ACPI
\par 
\par \tab\{Advanced Configuration and Power Interface\}
\par 
\par Acrobat
\par 
\par \tab <text, product> A product from \{Adobe Systems, Inc.\}, for
\par \tab manipulating documents stored in \{Portable Document Format\}.
\par \tab Acrobat provides a \{platform\}-independent means of creating,
\par \tab viewing, and printing documents.
\par 
\par \tab\{Acropolis: the magazine of Acrobat publishing
\par \tab (http://www.acropolis.com/acropolis)\}.
\par 
\par \tab (1995-04-21)
\par 
\par acronym
\par 
\par \tab <jargon> An identifier formed from some of the letters (often
\par \tab the initials) of a phrase and used as an abbreviation.  \{This
\par \tab dictionary\} contains a great many acronyms; see the contents
\par \tab page for a list.
\par 
\par \tab See also \{TLA\}.
\par 
\par \tab (1995-03-15)
\par 
\par ACSE
\par 
\par \tab\{Association Control Service Element\}
\par 
\par ACT
\par 
\par \tab 1. <software> \{Annual Change Traffic\}.
\par 
\par \tab 2. <company> \{Ada Core Technologies\}.
\par 
\par \tab (1999-06-24)
\par 
\par ACT++
\par 
\par \tab <language> A \{concurrent\} extension of \{C++\} based on
\par \tab\{actors\}.
\par 
\par \tab ["ACT++: Building a Concurrent C++ With Actors", D.G. Kafura
\par \tab TR89-18, VPI, 1989].
\par 
\par \tab (1994-11-08)
\par 
\par Act1
\par 
\par \tab <language> An \{actor\} language descended from \{Plasma\}.
\par 
\par \tab ["Concurrent Object Oriented Programming in Act1",
\par \tab H. Lieberman in Object Oriented Concurrent Programming,
\par \tab A. Yonezawa et al eds, MIT Press 1987].
\par 
\par \tab (1994-11-08)
\par 
\par Act2
\par 
\par \tab <language> An \{actor\} language.
\par 
\par \tab ["Issues in the Design of Act2", D. Theriault, TR728, MIT AI
\par \tab Lab, June 1983].
\par 
\par \tab (1994-11-08)
\par 
\par Act3
\par 
\par \tab <language> A high-level \{actor\} language by \{Carl Hewitt\}.  A
\par \tab descendant of \{Act2\} which provides support for automatic
\par \tab generation of \{customer\}s and for \{delegation\} and
\par \tab\{inheritance\}.
\par 
\par \tab ["Linguistic Support of Receptionists for Shared Resources",
\par \tab C. Hewitt et al in Seminar on Concurrency, S.D. Brookes et al
\par \tab eds, LNCS 197, Springer 1985, pp. 330-359].
\par 
\par \tab (1994-11-08)
\par 
\par Actalk
\par 
\par \tab <language> A \{Smalltalk\}-based \{actor\} language developed by
\par \tab J-P Briot in 1989.
\par 
\par \tab ["Actalk: A Testbed for Classifying and Designing Actor
\par \tab Languages in the Smalltalk-80 Environment", J-P. Briot, Proc
\par \tab ECOOP '89, pp. 109-129].
\par 
\par \tab (1994-11-08)
\par 
\par Actis
\par 
\par \tab <programming> An approach to integrated \{CASE\} by \{Apollo\}.
\par 
\par \tab (1994-11-08)
\par 
\par activation record
\par 
\par \tab <compiler> (Or "data frame", "stack frame") A data structure
\par \tab containing the variables belonging to one particular \{scope\}
\par \tab (e.g. a procedure body), as well as links to other activation
\par \tab records.
\par 
\par \tab Activation records are usually created (on the \{stack\}) on
\par \tab entry to a block and destroyed on exit.  If a procedure or
\par \tab function may be returned as a result, stored in a variable and
\par \tab used in an outer scope then its activation record must be
\par \tab stored in a \{heap\} so that its variables still exist when it
\par \tab is used.  Variables in the current \{scope\} are accessed via
\par \tab the \{frame pointer\} which points to the current activation
\par \tab record.  Variables in an outer scope are accessed by following
\par \tab chains of links between activation records.  There are two
\par \tab kinds of link - the \{static link\} and the \{dynamic link\}.
\par 
\par \tab (1995-03-07)
\par 
\par active DBMS
\par 
\par \tab <database> A conventional or passive \{DBMS\} combined with a
\par \tab means of event detection and condition monitoring.  Event
\par \tab handling is often rule-based, as with an \{expert system\}.
\par 
\par \tab (1994-11-08)
\par 
\par Active Directory
\par 
\par \tab <operating system> A \{directory service\} from \{Microsoft
\par \tab Corporation\}, similar in concept to \{Novell\} \{Netware
\par \tab Directory Services (NDS)\}, that also integrates with the user
\par \tab organisation's \{DNS\} structure and is interoperable with
\par \tab\{LDAP\}.  Active Directory is included in \{Windows 2000\}.
\par 
\par \tab (2000-03-28)
\par 
\par Active Language I
\par 
\par \tab <tool, mathematics> An early interactive mathematics system
\par \tab for the \{XDS 930\} at the \{University of California at
\par \tab Berkeley\}.
\par 
\par \tab ["Active Language I", R. de Vogelaere in Interactive Systems
\par \tab for Experimental Applied Mathematics, A-P 1968].
\par 
\par \tab (1994-11-08)
\par 
\par active matrix display
\par 
\par \tab <hardware> A type of \{liquid crystal display\} where each
\par \tab display element (each \{pixel\}) includes an active component
\par \tab such as a \{transistor\} to maintain its state between scans.
\par 
\par \tab Contrast \{passive matrix display\}.
\par 
\par \tab (1995-12-09)
\par 
\par Active Monitor
\par 
\par \tab <networking> A process in an \{IBM\} \{token ring\} network which
\par \tab ensures a token is present on the ring, removes circulating
\par \tab frames with unknown or invalid destinations, and performs
\par \tab introductions between machines on the ring.
\par 
\par \tab (1996-06-18)
\par 
\par active object
\par 
\par \tab <programming> An \{object\} each \{instance\} of which has its own
\par \tab\{thread\} running as well as its own copies of the object's
\par \tab\{instance variables\}.
\par 
\par \tab (1998-03-08)
\par 
\par Active Reconfiguring Message
\par 
\par \tab <hardware> (ARM) An efficient mechanism which allows
\par \tab reconfiguration of the hardware logic of a system according to
\par \tab the particular data received or transmitted.
\par 
\par \tab In ARM each message contains extra information in a
\par \tab Reconfiguring \{Header\} in addition to the data to be
\par \tab transferred.  Upon arrival of the message the Reconfiguring
\par \tab Header is extracted, decoded and used to perform on-the-fly
\par \tab hardware reconfiguration.  As soon as the hardware has been
\par \tab reconfigured the data information of the message can be
\par \tab processed.
\par 
\par \tab [In what contect is this term used?]
\par 
\par \tab (1997-06-06)
\par 
\par Active Server Pages
\par 
\par \tab <World-Wide Web, programming> (ASP) A \{scripting\} environment
\par \tab for \{Microsoft Internet Information Server\} in which you can
\par \tab combine \{HTML\}, scripts and reusable \{ActiveX\} \{server\}
\par \tab components to create dynamic \{web pages\}.
\par 
\par \tab IIS 4.0 includes scripting engines for \{Microsoft Visual
\par \tab Basic\} Scripting Edition (\{VBScript\}) and \{Microsoft JScript\}.
\par \tab\{ActiveX\} scripting engines for \{Perl\} and \{REXX\} are
\par \tab available through third-party developers.
\par 
\par \tab [URL?]
\par 
\par \tab (1999-12-02)
\par 
\par ActiveX
\par 
\par \tab <programming> A type of \{COM\} component that can
\par \tab self-register, also known as an "ActiveX control".  All COM
\par \tab objects implement the "IUnknown" interface but an ActiveX
\par \tab control usually also implements some of the standard
\par \tab interfaces for embedding, user interface, methods, properties,
\par \tab events, and persistence.
\par 
\par \tab ActiveX controls were originally called "\{OLE\} Controls", and
\par \tab were required to provide all of these interfaces but that
\par \tab requirement was dropped, and the name changed, to make ActiveX
\par \tab controls lean enough to be downloaded as part of a web page.
\par 
\par \tab Because ActiveX components can support the OLE embedding
\par \tab interfaces, they can be included in web pages.  Because they
\par \tab are COM objects, they can be used from languages such as
\par \tab\{Visual Basic\}, \{Visual C++\}, \{Java\}, \{VBScript\}.
\par 
\par \tab ["Understanding ActiveX and OLE", David Chappell, MS Press,
\par \tab 1996].
\par 
\par \tab\{Home (http://www.microsoft.com/com/tech/activex.asp)\}.
\par 
\par \tab (2002-04-19)
\par 
\par ACT ONE
\par 
\par \tab <language, specification> A specification language.
\par 
\par \tab ["An Algebraic Specification Language with Two Levels of
\par \tab Semantics", H. Ehrig et al, Tech U Berlin 83-1983-02-03].
\par 
\par \tab (1994-11-08)
\par 
\par Actor
\par 
\par \tab <language> An \{object-oriented\} language for \{Microsoft
\par \tab Windows\} written by Charles Duff of the \{Whitewater Group\} ca.
\par \tab 1986.  It has \{Pascal\}/\{C\}-like \{syntax\}.  Uses a
\par \tab\{token-threaded\} \{interpreter\}.  \{Early binding\} is an option.
\par 
\par \tab ["Actor Does More than Windows", E.R. Tello, Dr Dobb's J
\par \tab 13(1):114-125 (Jan 1988)].
\par 
\par \tab (1994-11-08)
\par 
\par actor
\par 
\par \tab 1. <programming> In \{object-oriented\} programming, an \{object\}
\par \tab which exists as a \{concurrent\} process.
\par 
\par \tab 2. <operating system> In \{Chorus\}, the unit of resource
\par \tab allocation.
\par 
\par \tab (1994-11-08)
\par 
\par Actors
\par 
\par \tab <theory> A model for \{concurrency\} by \{Carl Hewitt\}.  Actors
\par \tab are autonomous and concurrent \{objects\} which execute
\par \tab\{asynchronously\}.  The Actor model provides flexible
\par \tab mechanisms for building parallel and \{distributed\} software
\par \tab systems.
\par 
\par \tab\{(http://osl.cs.uiuc.edu/)\}.
\par 
\par \tab ["Laws for Communicating Parallel Processes", C. Hewitt et al,
\par \tab IFIP 77, pp. 987-992, N-H 1977].
\par 
\par \tab ["ACTORS: A Model of Concurrent Computation in Distributed
\par \tab Systems", Gul A. Agha <agha@cs.uiuc.edu>, Cambridge Press, MA,
\par \tab 1986].
\par 
\par \tab (1999-11-23)
\par 
\par actor/singer/waiter/webmaster
\par 
\par \tab <World-Wide Web> An elaboration of the ages-old concept of the
\par \tab actor/singer/waiter, the actor/singer/waiter/webmaster is
\par \tab someone who waits tables /for now/, but who has aspirations of
\par \tab breaking into the glamorous worlds of acting or New Media or
\par \tab both!
\par 
\par \tab He keeps going to auditions and sending a resumes to \{C|Net
\par \tab (http://www.cnet.com)\} -- because you have to pay your dues.
\par 
\par \tab His credits include being on "Friends" (as an extra), in "ER"
\par \tab (actually, in an ER -- he twisted his ankle once; but he
\par \tab counts the x-rays as screen credits), and having been the
\par \tab webmaster of an extensive multimedia interactive Web site (his
\par \tab hotlist of "Simpsons" links).
\par 
\par \tab (1998-04-04)
\par 
\par Actra
\par 
\par \tab <language> A \{multi-processor\} \{exemplar\}-based \{Smalltalk\}.
\par 
\par \tab [LaLonde et al, OOPSLA '86].
\par 
\par \tab (1994-11-08)
\par 
\par Actus
\par 
\par \tab <language> \{Pascal\} with parallel extensions, similar to the
\par \tab earlier \{Glypnir\}.  It has parallel constants and \{index
\par \tab set\}s.  Descendants include \{Parallel Pascal\}, \{Vector C\} and
\par \tab\{CMU\}'s language \{PIE\}.
\par 
\par \tab ["A Language for Array and Vector Processors," R.H. Perrott,
\par \tab ACM TOPLAS 1(2):177-195 (Oct 1979)].
\par 
\par \tab (1994-11-08)
\par 
\par AD
\par 
\par \tab\{Administrative Domain\}
\par 
\par ad
\par 
\par \tab <networking> The \{country code\} for Andorra.
\par 
\par \tab (1999-01-26)
\par 
\par Ada
\par 
\par \tab <language> (After \{Ada Lovelace\}) A \{Pascal\}-descended
\par \tab language, designed by Jean Ichbiah's team at \{CII Honeywell\}
\par \tab in 1979, made mandatory for Department of Defense software
\par \tab projects by the Pentagon.  The original language was
\par \tab standardised as "Ada 83", the latest is "\{Ada 95\}".
\par 
\par \tab Ada is a large, complex, \{block-structured\} language aimed
\par \tab primarily at \{embedded\} applications.  It has facilities for
\par \tab\{real-time\} response, \{concurrency\}, hardware access and
\par \tab reliable run-time error handling.  In support of large-scale
\par \tab\{software engineering\}, it emphasises \{strong typing\}, \{data
\par \tab abstraction\} and \{encapsulation\}.  The type system uses \{name
\par \tab equivalence\} and includes both \{subtype\}s and \{derived type\}s.
\par \tab Both fixed and \{floating-point\} numerical types are supported.
\par 
\par \tab\{Control flow\} is fully bracketed: if-then-elsif-end if,
\par \tab case-is-when-end case, loop-exit-end loop, goto.  Subprogram
\par \tab parameters are in, out, or inout.  Variables imported from
\par \tab other packages may be hidden or directly visible.  Operators
\par \tab may be \{overloaded\} and so may \{enumeration\} literals.  There
\par \tab are user-defined \{exception\}s and \{exception handler\}s.
\par 
\par \tab An Ada program consists of a set of packages encapsulating
\par \tab data objects and their related operations.  A package has a
\par \tab separately compilable body and interface.  Ada permits
\par \tab\{generic package\}s and subroutines, possibly parametrised.
\par 
\par \tab Ada support \{single inheritance\}, using "tagged types" which
\par \tab are types that can be extended via \{inheritance\}.
\par 
\par \tab Ada programming places a heavy emphasis on \{multitasking\}.
\par \tab Tasks are synchronised by the \{rendezvous\}, in which a task
\par \tab waits for one of its subroutines to be executed by another.
\par \tab The conditional entry makes it possible for a task to test
\par \tab whether an entry is ready.  The selective wait waits for
\par \tab either of two entries or waits for a limited time.
\par 
\par \tab Ada is often criticised, especially for its size and
\par \tab complexity, and this is attributed to its having been designed
\par \tab by committee.  In fact, both Ada 83 and Ada 95 were designed
\par \tab by small design teams to be internally consistent and tightly
\par \tab integrated.  By contrast, two possible competitors, \{Fortran
\par \tab 90\} and \{C++\} have both become products designed by large and
\par \tab disparate volunteer committees.
\par 
\par \tab See also \{Ada/Ed\}, \{Toy/Ada\}.
\par 
\par \tab\{Home of the Brave Ada Programmers
\par \tab (http://lglwww.epfl.ch/Ada/)\}.  \{Ada FAQs
\par \tab (http://lglwww.epfl.ch/Ada/FAQ/)\} (hypertext), \{text only
\par \tab (ftp://lglftp.epfl.ch/pub/Ada/FAQ)\}.
\par 
\par \tab\{(http://wuarchive.wustl.edu/languages/ada/)\},
\par \tab\{(ftp://ajpo.sei.cmu.edu/)\},
\par \tab\{(ftp://stars.rosslyn.unisys.com/pub/ACE_8.0)\}.
\par 
\par \tab E-mail: <adainfo@ajpo.sei.cmu.edu>.
\par 
\par \tab\{Usenet\} newsgroup: \{news:comp.lang.ada\}.
\par 
\par \tab\{An Ada grammar (ftp://primost.cs.wisc.edu/)\} including a lex
\par \tab scanner and yacc parser is available.  E-mail:
\par \tab <masticol@dumas.rutgers.edu>.
\par 
\par \tab\{Another yacc grammar and parser for Ada by Herman Fischer
\par \tab (ftp://wsmr-simtel20.army.mil/PD2:<ADA.EXTERNAL-TOOLS>GRAM2.SRC)\}.
\par 
\par \tab An \{LR parser\} and \{pretty-printer\} for \{Ada\} from NASA is
\par \tab available from the \{Ada Software Repository\}.
\par 
\par \tab\{Adamakegen\} generates \{makefiles\} for \{Ada\} programs.
\par 
\par \tab ["Reference Manual for the Ada Programming Language", ANSI/MIL
\par \tab STD 1815A, US DoD (Jan 1983)].  Earlier draft versions
\par \tab appeared in July 1980 and July 1982.  ISO 1987.
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (2000-08-12)
\par 
\par Ada++
\par 
\par \tab <language> An \{object-oriented\} extension to \{Ada\},
\par \tab implemented as an Ada \{preprocessor\}.  Obsoleted by \{Ada 95\}
\par \tab which includes object-oriented features.
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (1995-09-19)
\par 
\par Ada 83
\par 
\par \tab <language> The original \{Ada\}, as opposed to \{Ada 95\}.
\par 
\par \tab (1995-03-13)
\par 
\par Ada 95
\par 
\par \tab <language> A revision and extension of \{Ada\} (Ada 83) begun in
\par \tab 1988 and completed on 1994-12-01 by a team lead by Tucker Taft
\par \tab of \{Intermetrics\}.  Chris Anderson was the Project Manager.
\par \tab The printed standard was expected to be available around
\par \tab 1995-02-15.
\par 
\par \tab Additions include \{object-orientation\} (\{tagged types\},
\par \tab\{abstract types\} and \{class-wide types\}), hierarchical
\par \tab libraries and synchronisation with shared data (protected
\par \tab types) similar to \{Orca\}.  It lacks \{multiple inheritance\} but
\par \tab supports the construction of multiple inheritance type
\par \tab hierarchies through the use of \{generics\} and \{type
\par \tab composition\}.
\par 
\par \tab\{GNAT\} aims to be a free implementation of Ada 95.
\par 
\par \tab You can get the standard from the \{Ada Joint Program Office
\par \tab (http://wuarchive.wustl.edu/languages/ada/ajpo/index.shtml)\}.
\par 
\par \tab ["Introducing Ada 9X", J.G.P. Barnes, Feb 1993].
\par 
\par \tab (1999-12-02)
\par 
\par Ada 9X
\par 
\par \tab <language> The working title for \{Ada 95\} before its adoption
\par \tab as an \{ISO\} \{standard\}.
\par 
\par \tab (1995-01-19)
\par 
\par ADABAS
\par 
\par \tab <database> A \{relational database\} system by \{Software AG\}.
\par \tab While it was initially designed for large \{IBM\} \{mainframe\}
\par \tab systems (e.g. \{S/370\} in the late 1970s), it has been ported
\par \tab to numerous other \{platform\}s over the last few years such as
\par \tab several flavors of \{Unix\} including \{AIX\}.
\par 
\par \tab ADABAS stores its data in tables (and is thus "relational")
\par \tab but also uses some non-relational techniques, such as
\par \tab\{multiple value\}s and \{periodic group\}s.
\par 
\par \tab (1995-10-30)
\par 
\par Ada Core Technologies
\par 
\par \tab <company> (ACT) The company that maintains \{GNAT\}.
\par 
\par \tab Ada Core Technologies was founded in 1994 by the original
\par \tab authors of the GNAT compiler.  ACT provides software for \{Ada
\par \tab 95\} development.
\par 
\par \tab\{Home (http://www.gnat.com/)\}.
\par 
\par \tab (2000-10-28)
\par 
\par Ada/Ed
\par 
\par \tab <language, education> An \{interpreter\}, editor, and \{run-time
\par \tab environment\} for \{Ada\}, intended as a teaching tool.  Ada/Ed
\par \tab does not have the capacity, performance, or robustness of
\par \tab commercial Ada compilers.  Ada/Ed was developed at \{New York
\par \tab University\} as part of a project in language definition and
\par \tab software prototyping.
\par 
\par \tab AdaEd runs on \{Unix\}, \{MS-DOS\}, \{Atari ST\}, and \{Amiga\}.
\par 
\par \tab It handles nearly all of \{Ada 83\} and was last validated with
\par \tab version 1.7 of the \{ACVC\} tests.  Being an interpreter, it
\par \tab does not implement most \{representation clause\}s and thus does
\par \tab not support systems programming close to the machine level.
\par 
\par \tab Latest version: 1.11.0a+, as of 1994-08-18.  A later version
\par \tab is known as \{GW-Ada\}.
\par 
\par \tab E-mail: Michael Feldman <mfeldman@seas.gwu.edu>.
\par 
\par \tab\{(ftp://ftp.wustl.edu/amiga/languages/ada)\},
\par \tab\{(ftp://cnam.cnam.fr/pub/Ada/Ada-Ed)\}.  \{For Amiga
\par \tab (ftp://cs.nyu.edu/pub/adaed)\}.
\par 
\par \tab\{RISC OS port
\par \tab (ftp://micros.hensa.ac.uk/micros/arch/riscos/c/c052)\}.
\par 
\par \tab (1999-11-04)
\par 
\par Adaline
\par 
\par \tab <architecture> Name given by Widrow to \{adaptive linear
\par \tab neuron\}s, that is \{neuron\}s (see \{McCulloch-Pitts\}) which
\par \tab learn using the \{Widrow-Huff Delta Rule\}.  See also
\par \tab\{Madaline\}.
\par 
\par \tab (1995-03-14)
\par 
\par Ada Lovelace
\par 
\par \tab <person> (1811-1852) The daughter of Lord Byron, who became
\par \tab the world's first programmer while cooperating with \{Charles
\par \tab Babbage\} on the design of his mechanical computing engines in
\par \tab the mid-1800s.
\par 
\par \tab The language \{Ada\} was named after her.
\par 
\par \tab [\{"Ada, Enchantress of Numbers Prophit of the Computer Age",
\par \tab Betty Alexandra Toole (http://www.well.com/user/adatoole)\}].
\par 
\par \tab [More details?]
\par 
\par \tab (1999-07-17)
\par 
\par ADAM
\par 
\par \tab\{A Data Management system\}
\par 
\par Adam7
\par 
\par \tab <graphics, algorithm> One of the \{progressive coding\} methods
\par \tab used in \{PNG\} \{images\}.  Adam7, named after its author, Adam
\par \tab M. Costello, consists of seven distinct passes over the image.
\par \tab Each pass transmits a subset of the \{pixels\} in the image.
\par \tab The pass in which each pixel is transmitted is defined by
\par \tab replicating the following 8-by-8 pattern over the entire
\par \tab image, starting at the top left:
\par 
\par \tab  1 6 4 6 2 6 4 6
\par \tab  7 7 7 7 7 7 7 7
\par \tab  5 6 5 6 5 6 5 6
\par \tab  7 7 7 7 7 7 7 7
\par \tab  3 6 4 6 3 6 4 6
\par \tab  7 7 7 7 7 7 7 7
\par \tab  5 6 5 6 5 6 5 6
\par \tab  7 7 7 7 7 7 7 7
\par 
\par \tab (2000-09-12)
\par 
\par Adamakegen
\par 
\par \tab <tool> A program that generates \{makefiles\} for \{Ada\}
\par \tab programs.  Adamakegen was written by Owen O'Malley
\par \tab <owen-omalley@home.net>.  It requires \{Icon\} and runs under
\par \tab\{Verdix\} and \{SunAda\}.
\par 
\par \tab Current version: 2.6.3, as of 1993-03-02.
\par 
\par \tab\{Home (http://members.home.net/owenomalley/adamakegen.html)\}.
\par 
\par \tab (2001-11-07)
\par 
\par ADAMO
\par 
\par \tab <database> A data management system written at CERN based on
\par \tab the \{Entity-Relationship model\}.
\par 
\par \tab (1995-03-14)
\par 
\par Ada-O
\par 
\par \tab <language> An \{Ada\} subset developed at the \{University of
\par \tab Karlsruhe\} in 1979, used for \{compiler\} \{bootstrapping\}.  It
\par \tab lacks \{overloading\}, \{derived type\}s, \{real number\}s, tasks
\par \tab and \{generic\}s.
\par 
\par \tab ["Revised Ada-O Reference Manual", G. Persch et al, U
\par \tab Karlsruhe, Inst fur Infor II, Bericht Nr 9/81].
\par 
\par \tab (1995-02-14)
\par 
\par Adaplan
\par 
\par \tab <language> A \{functional database\} language based upon
\par \tab\{Backus\}' \{FP\} language.
\par 
\par \tab [Erwig&Lipeck, Proc. DBPL-3, 1991].
\par 
\par \tab (1995-05-07)
\par 
\par Adaplex
\par 
\par \tab <language, database> An extension of \{Ada\} for \{functional
\par \tab database\}s.
\par 
\par \tab ["Adaplex: Rationale and Reference Manual 2nd ed", J.M. Smith
\par \tab et al, Computer Corp America, Cambridge MA, 1983].
\par 
\par \tab (1995-02-14)
\par 
\par Ada Programming Support Environment
\par 
\par \tab <tool, project> (APSE) A program or set of programs to support
\par \tab software development in the Ada language.
\par 
\par \tab [Examples?]
\par 
\par \tab (1997-06-30)
\par 
\par ADAPT
\par 
\par \tab <language> A subset of \{APT\}.
\par 
\par \tab [Sammet 1969, p. 606].
\par 
\par \tab (1995-02-14)
\par 
\par Adaptable User Interface
\par 
\par \tab <tool, product> (AUI, Oracle Toolkit) A toolkit from \{Oracle\}
\par \tab allowing applications to be written which will be portable
\par \tab between different \{windowing systems\}.  AUI provides one \{call
\par \tab level interface\} along with a resource manager and editor
\par \tab across a range of "standard" \{GUI\}s, including \{Macintosh\},
\par \tab\{Microsoft Windows\} and the \{X Window System\}.
\par 
\par \tab (1995-03-16)
\par 
\par Adaptec
\par 
\par \tab <company> A company specialising in the aera of movement of
\par \tab data between computers.  Adaptec designs hardware and software
\par \tab products to transfer data from a computer to a \{peripheral\}
\par \tab device or \{network\}.
\par 
\par \tab Founded in 1981, the company achieved profitability in 1984,
\par \tab went public in 1986, and to date has achieved 54 consecutive
\par \tab profitable quarters.
\par 
\par \tab Revenues for fiscal 1997 were $934 million, a 42% increase
\par \tab over the prior year.  Net income, excluding acquisition
\par \tab charges, for fiscal year 1997 was $198 million or $1.72 per
\par \tab share.
\par 
\par \tab\{Home (http://www.adaptec.com)\}.
\par 
\par \tab (1999-08-25)
\par 
\par adaptive answering
\par 
\par \tab <communications> A feature which allows a \{faxmodem\} to answer
\par \tab the telephone and decide whether the incoming call is a fax or
\par \tab data call.  Most \{Class 1\} faxmodems do this.  The
\par \tab\{U.S. Robotics\} Class 1 implementation however seems not to do
\par \tab it, it must be set to answer as either one or the other.
\par 
\par \tab (1995-03-16)
\par 
\par Adaptive Communication Environment
\par 
\par \tab <communications, tool> A \{C++\} wrapper library for
\par \tab communications from the \{University of California at Irvine\}.
\par 
\par \tab (1995-03-16)
\par 
\par Adaptive Digital Pulse Code Modulation
\par 
\par \tab <communications> (ADPCM) A \{compression\} technique which
\par \tab records only the difference between samples and adjusts the
\par \tab coding scale dynamically to accomodate large and small
\par \tab differences.  ADPCM is simple to implement, but introduces
\par \tab much \{noise\}.
\par 
\par \tab [Used where?  Does the \{Sony\} minidisk use ADPCM or \{ATRAC\}?]
\par 
\par \tab (1998-12-10)
\par 
\par adaptive learning
\par 
\par \tab <algorithm> (Or "\{Hebbian\} learning") Learning where a system
\par \tab programs itself by adjusting weights or strengths until it
\par \tab produces the desired output.
\par 
\par \tab (1995-03-16)
\par 
\par adaptive routing
\par 
\par \tab\{dynamic routing\}
\par 
\par Adaptive Simulated Annealing
\par 
\par \tab <language> (ASA) An \{algorithm\} for global optimisation of
\par \tab generic \{functions\} by Lester Ingber
\par \tab <ingber@alumni.caltech.edu> <ingber@ingber.com>.
\par 
\par \tab Latest version: 20.5, as of 2000-02-29.
\par 
\par \tab\{Home (http://www.alumni.caltech.edu/~ingber/)\}.
\par 
\par \tab\{Home (http://www.ingber.com/)\}.
\par 
\par \tab Mailing list: <asa-request@alumni.caltech.edu>.
\par 
\par \tab (2000-02-29)
\par 
\par Adaptive TRansform Acoustic Coding
\par 
\par \tab <algorithm> (ATRAC) An audio compression \{algorithm\},
\par \tab introduced by \{Sony\} for its \{Mini Disk\}, which relies on the
\par \tab masking of low-amplitude frequency components by temporaly
\par \tab adjacent high-amplitude components.  ATRAC consists of a
\par \tab three-band \{subband encoder\} (0...5.5, 5.5...11, 11...22 kHz)
\par \tab and a \{MDCT\} based transformation encoder.
\par 
\par \tab [Does Sony Minidisk use \{ADPCM\}?]
\par 
\par \tab (2001-12-13)
\par 
\par Adaptor
\par 
\par \tab <tool> (Automatic DAta Parallelism TranslatOR) A source to
\par \tab source transformation tool that transforms \{data parallel\}
\par \tab programs written in \{Fortran 77\} with \{array\} extensions,
\par \tab parallel loops, and layout directives to parallel programs
\par \tab with explicit \{message passing\}.  ADAPTOR generates \{Fortran
\par \tab 77\} host and node programs with message passing.  The new
\par \tab generated source codes have to be compiled by the compiler of
\par \tab the parallel computer.
\par 
\par \tab Version 1.0 runs on \{CM-5\}, \{iPCS/860\}, \{Meiko CS1\}/CS2, \{KSR
\par \tab 1\}, \{SGI\}, \{Alliant\} or a network of \{Sun\}s or \{RS/6000\}s.
\par 
\par \tab\{(ftp://ftp.gmd.de/gmd/adaptor/adp_1.0.tar.Z)\}.
\par 
\par \tab [Connection with Thomas Brandes and GMD?]
\par 
\par \tab (1993-06-01)
\par 
\par Ada Semantic Interface Specification
\par 
\par \tab <language> (ASIS) An intermediate representation for \{Ada\}.
\par 
\par \tab E-mail: <sblake@thomsoft.com>.
\par 
\par \tab See also \{Diana\}.
\par 
\par \tab (1995-02-15)
\par 
\par Ada Software Repository
\par 
\par \tab <language> A collection of \{Ada\} programs?
\par 
\par \tab\{Home (http://wuarchive.wustl.edu/languages/ada/asr/)\}.
\par 
\par \tab (1995-01-06)
\par 
\par ADC
\par 
\par \tab\{Analog to Digital Converter\}
\par 
\par ADCCP
\par 
\par \tab\{Advanced Data Communications Control Protocol\}
\par 
\par A/D converter
\par 
\par \tab\{Analog to Digital Converter\}
\par 
\par ADCU
\par 
\par \tab\{application developer customer unit\}
\par 
\par AD/Cycle
\par 
\par \tab <tool, product> Application Development cycle.
\par 
\par \tab A set of \{SAA\}-compatible \{IBM\}-sponsored products for program
\par \tab development, running on workstations accessing a central
\par \tab repository on a \{mainframe\}.  The stages cover requirements,
\par \tab analysis and design, production of the application, building
\par \tab and testing and maintenance.  Technologies used include code
\par \tab generators and \{knowledge based system\}s as well as languages
\par \tab and debuggers.
\par 
\par \tab (1994-10-24)
\par 
\par ADD 1 TO COBOL GIVING COBOL
\par 
\par \tab <humour, language> (From COBOL's equivalent syntax to C's C++)
\par \tab A tongue-in-cheek suggestion by Bruce Clement for an
\par \tab\{object-oriented\} \{COBOL\}.
\par 
\par \tab [SIGPLAN Notices 27(4):90-91 (Apr 1992)].
\par 
\par \tab (1995-03-17)
\par 
\par ADDD
\par 
\par \tab <tool> A Depository of Development Documents.
\par 
\par \tab A \{public domain\} Software Engineering Environment from \{GMD\}
\par \tab developed as part of the \{STONE\} project.
\par 
\par \tab (1995-02-03)
\par 
\par additive
\par 
\par \tab <mathematics> A function f : X -> Y is additive if
\par 
\par \tab  for all Z <= X
\par \tab  f (lub Z)  =  lub \{ f z : z in Z \}
\par 
\par \tab (f "preserves \{lub\}s").  All additive functions defined over
\par \tab\{cpo\}s are \{continuous\}.
\par 
\par \tab ("<=" is written in \{LaTeX\} as \{\\subseteq\}, "lub" as \\sqcup ).
\par 
\par \tab (1995-02-03)
\par 
\par address
\par 
\par \tab 1. <networking> \{e-mail address\}.
\par 
\par \tab 2. <networking> \{Internet address\}.
\par 
\par \tab 3. <networking> \{MAC address\}.
\par 
\par \tab 4. <storage, programming> An unsigned integer used to select
\par \tab one fundamental element of storage, usually known as a \{word\}
\par \tab from a computer's \{main memory\} or other storage device.  The
\par \tab\{CPU\} outputs addresses on its \{address bus\} which may be
\par \tab connected to an \{address decoder\}, \{cache controller\}, \{memory
\par \tab management unit\}, and other devices.
\par 
\par \tab While from a hardware point of view an address is indeed an
\par \tab integer most \{strongly typed\} programming languages disallow
\par \tab mixing integers and addresses, and indeed addresses of
\par \tab different data types.  This is a fine example for \{syntactic
\par \tab salt\}: the compiler could work without it but makes writing
\par \tab bad programs more difficult.
\par 
\par \tab (1997-07-01)
\par 
\par address bus
\par 
\par \tab <processor> The connections between the \{CPU\} and memory which
\par \tab carry the \{address\} from/to which the CPU wishes to read or
\par \tab write.  The number of bits of address bus determines the
\par \tab maximum size of memory which the processor can access.
\par 
\par \tab See also \{data bus\}.
\par 
\par \tab (1995-03-22)
\par 
\par addressed call mode
\par 
\par \tab <communications> (ACM) A mode that permits control signals and
\par \tab commands to establish and terminate calls in \{V.25bis\}.
\par 
\par \tab (1997-05-07)
\par 
\par addressee
\par 
\par \tab <communications> One to whom something is addressed.
\par \tab E.g. "The To, CC, and \{BCC\} \{headers\} list the addressees of
\par \tab the e-mail message".  Normally an addressee will eventually be
\par \tab a \{recipient\}, unless there is a failure at some point (an
\par \tab e-mail "\{bounces\}") or the message is redirected to a
\par \tab different addressee.
\par 
\par \tab (2000-03-22)
\par 
\par addressing mode
\par 
\par \tab 1. <processor, programming> One of a set of methods for
\par \tab specifying the \{operand\}(s) for a \{machine code\} instruction.
\par \tab Different processors vary greatly in the number of addressing
\par \tab modes they provide.  The more complex modes described below
\par \tab can usually be replaced with a short sequence of instructions
\par \tab using only simpler modes.
\par 
\par \tab The most common modes are "register" - the operand is stored
\par \tab in a specified \{register\}; "absolute" - the operand is stored
\par \tab at a specified memory address; and "\{immediate\}" - the operand
\par \tab is contained within the instruction.
\par 
\par \tab Most processors also have \{indirect addressing\} modes, e.g.
\par \tab "register indirect", "memory indirect" where the specified
\par \tab register or memory location does not contain the operand but
\par \tab contains its address, known as the "\{effective address\}".  For
\par \tab an absolute addressing mode, the effective address is
\par \tab contained within the instruction.
\par 
\par \tab Indirect addressing modes often have options for pre- or post-
\par \tab increment or decrement, meaning that the register or memory
\par \tab location containing the \{effective address\} is incremented or
\par \tab decremented by some amount (either fixed or also specified in
\par \tab the instruction), either before or after the instruction is
\par \tab executed.  These are very useful for \{stack\}s and for
\par \tab accessing blocks of data.  Other variations form the effective
\par \tab address by adding together one or more registers and one or
\par \tab more constants which may themselves be direct or indirect.
\par \tab Such complex addressing modes are designed to support access
\par \tab to multidimensional arrays and arrays of data structures.
\par 
\par \tab The addressing mode may be "implicit" - the location of the
\par \tab operand is obvious from the particular instruction.  This
\par \tab would be the case for an instruction that modified a
\par \tab particular control register in the CPU or, in a \{stack\} based
\par \tab processor where operands are always on the top of the stack.
\par 
\par \tab 2. In \{IBM\} \{System 370\}/\{XA\} the addressing mode bit controls
\par \tab the size of the \{effective address\} generated.  When this bit
\par \tab is zero, the CPU is in the 24-bit addressing mode, and 24 bit
\par \tab instruction and operand effective addresses are generated.
\par \tab When this bit is one, the CPU is in the 31-bit addressing
\par \tab mode, and 31-bit instruction and operand effective addresses
\par \tab are generated.
\par 
\par \tab ["IBM System/370 Extended Architecture Principles of
\par \tab Operation", Chapter 5., 'Address Generation', BiModal
\par \tab Addressing].
\par 
\par \tab (1995-03-30)
\par 
\par address mask
\par 
\par \tab <networking> (Or "subnet mask") A \{bit mask\} used to identify
\par \tab which bits in an \{IP address\} correspond to the \{network
\par \tab address\} and \{subnet\} portions of the address.  This mask is
\par \tab often referred to as the subnet mask because the network
\par \tab portion of the address can be determined by the \{class\}
\par \tab inherent in an IP address.  The address mask has ones in
\par \tab positions corresponding to the network and subnet numbers and
\par \tab zeros in the host number positions.
\par 
\par \tab (1996-03-21)
\par 
\par address resolution
\par 
\par \tab <networking> Conversion of an \{Internet address\} into the
\par \tab corresponding physical address (\{Ethernet address\}).  This is
\par \tab usually done using \{Address Resolution Protocol\}.
\par 
\par \tab The \{resolver\} is a library routine and a set of processes
\par \tab which converts \{hostnames\} into \{Internet addresses\}, though
\par \tab this process in not usually referred to as \{resolution\}.  See
\par \tab\{DNS\}.
\par 
\par \tab (1996-04-09)
\par 
\par Address Resolution Protocol
\par 
\par \tab <networking, protocol> (ARP) A method for finding a \{host\}'s
\par \tab\{Ethernet address\} from its \{Internet address\}.  The sender
\par \tab broadcasts an ARP \{packet\} containing the \{Internet address\}
\par \tab of another host and waits for it (or some other host) to send
\par \tab back its Ethernet address.  Each host maintains a \{cache\} of
\par \tab address translations to reduce delay and loading.  ARP allows
\par \tab the Internet address to be independent of the Ethernet address
\par \tab but it only works if all hosts support it.
\par 
\par \tab ARP is defined in \{RFC 826\}.
\par 
\par \tab The alternative for hosts that do not do ARP is \{constant
\par \tab mapping\}.
\par 
\par \tab See also \{proxy ARP\}, \{reverse ARP\}.
\par 
\par \tab (1995-03-20)
\par 
\par address space
\par 
\par \tab <operating system, architecture> The range of addresses which
\par \tab a processor or process can access, or at which a \{device\} can
\par \tab be accessed.  The term may refer to either \{physical address\}
\par \tab or \{virtual address\}.
\par 
\par \tab The size of a processor's address space depends on the width
\par \tab of the processor's \{address bus\} and address \{registers\}.
\par 
\par \tab Each device, such as a memory \{integrated circuit\}, will have
\par \tab its own local address space which starts at zero.  This will
\par \tab be mapped to a range of addresses which starts at some base
\par \tab address in the processor's address space.
\par 
\par \tab Similarly, each \{process\} will have its own address space,
\par \tab which may be all or a part of the processor's address space.
\par \tab In a \{multitasking\} system this may depend on where in memory
\par \tab the process happens to have been loaded.  For a process to be
\par \tab able to run at any address it must consist of
\par \tab\{position-independent code\}.  Alternatively, each process may
\par \tab see the same local address space, with the \{memory management
\par \tab unit\} mapping this to the process's own part of the
\par \tab processor's address space.
\par 
\par \tab (1999-11-01)
\par 
\par Address Strobe
\par 
\par \tab <storage> (AS) One of the input signals of a memory device,
\par \tab especially \{semiconductor\} memory, which is asserted to tell
\par \tab the memory device that the \{address\} inputs are valid.  Upon
\par \tab receiving this signal the selected memory device starts the
\par \tab memory access (read/write) indicated by its other inputs.
\par 
\par \tab It may be driven directly by the \{processor\} or by a \{memory
\par \tab controller\}.
\par 
\par \tab (1996-10-02)
\par 
\par ADELE
\par 
\par \tab <language> A language for specification of \{attribute
\par \tab grammar\}s, used by the \{MUG2\} \{compiler compiler\}.
\par 
\par \tab ["An Overview of the Attribute Definition Language ADELE",
\par \tab H. Ganziger in GI3, Fachesprach "Compiler-Compiler",
\par \tab W. Henhapl ed, Munchen Mar 1982, pp.22-53].
\par 
\par \tab (1995-01-23)
\par 
\par ADES
\par 
\par \tab <language> An early system on the \{IBM 704\}.
\par 
\par \tab Version: ADES II.
\par 
\par \tab [Listed in CACM 2(5):16 (May 1959)].
\par 
\par \tab (1995-03-20)
\par 
\par ad hoc
\par 
\par \tab Contrived purely for the purpose in hand rather than planned
\par \tab carefully in advance.  E.g. "We didn't know what to do about
\par \tab the sausage rolls, so we set up an ad-hoc committee".
\par 
\par \tab (1995-03-25)
\par 
\par ad-hockery
\par 
\par \tab <jargon> /ad-hok'*r-ee/ (Purdue) 1. Gratuitous assumptions
\par \tab made inside certain programs, especially \{expert system\}s,
\par \tab which lead to the appearance of semi-intelligent behaviour but
\par \tab are in fact entirely arbitrary.  For example, \{fuzzy-matching\}
\par \tab of input tokens that might be typing errors against a symbol
\par \tab table can make it look as though a program knows how to spell.
\par 
\par \tab 2. Special-case code to cope with some awkward input that
\par \tab would otherwise cause a program to fail, presuming normal
\par \tab inputs are dealt with in some cleaner and more regular way.
\par \tab Also called "ad-hackery", "ad-hocity" (/ad-hos'*-tee/),
\par \tab "ad-crockery".
\par 
\par \tab See also \{ELIZA effect\}.
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (1995-01-05)
\par 
\par ad-hoc polymorphism
\par 
\par \tab\{overloading\}
\par 
\par Aditi
\par 
\par \tab <database, project> The Aditi Deductive Database System.  A
\par \tab multi-user \{deductive database\} system from the Machine
\par \tab Intelligence Project at the \{University of Melbourne\}.  It
\par \tab supports base \{relations\} defined by \{facts\} (relations in the
\par \tab sense of \{relational databases\}) and \{derived relations\}
\par \tab defined by \{rules\} that specify how to compute new information
\par \tab from old information.
\par 
\par \tab Both base relations and the rules defining derived relations
\par \tab are stored on disk and are accessed as required during query
\par \tab evaluation.  The rules defining derived relations are
\par \tab expressed in a \{Prolog\}-like language, which is also used for
\par \tab expressing queries.
\par 
\par \tab Aditi supports the full structured data capability of Prolog.
\par \tab Base relations can store arbitrarily nested terms, for example
\par \tab arbitrary length lists, and rules can directly manipulate such
\par \tab terms.  Base relations can be indexed with \{B-trees\} or
\par \tab multi-level signature files.
\par 
\par \tab Users can access the system through a \{Motif\}-based query and
\par \tab database administration tool, or through a command line
\par \tab interface.  There is also in interface that allows \{NU-Prolog\}
\par \tab programs to access Aditi in a transparent manner.  Proper
\par \tab\{transaction processing\} is not supported in this release.
\par 
\par \tab The beta release runs on \{SPARC\}/\{SunOS4\}.1.2 and
\par \tab\{MIPS\}/\{Irix\}4.0.
\par 
\par \tab E-mail: <aditi@cs.mu.oz.au>.
\par 
\par \tab (1992-12-17)
\par 
\par adjacency
\par 
\par \tab <networking> A relationship between two \{network\} devices,
\par \tab e.g. \{routers\}, which are connected by one media segment so
\par \tab that a packet sent by one can reach the other without going
\par \tab through another network device.  The concept of adjacency is
\par \tab important in the exchange of routing information.
\par 
\par \tab Adjacent \{SNA\} \{nodes\} are nodes connected to a given node
\par \tab with no intervening nodes.  In \{DECnet\} and \{OSI\}, adjacent
\par \tab nodes share a common segment (\{Ethernet\}, \{FDDI\}, \{Token
\par \tab Ring\}).
\par 
\par \tab (1998-03-10)
\par 
\par adjacent
\par 
\par \tab\{adjacency\}
\par 
\par ADL
\par 
\par \tab 1. <games> \{Adventure Definition Language\}.
\par 
\par \tab 2. <language> \{Ada\} Development Language.
\par 
\par \tab R.A. Lees, 1989.
\par 
\par \tab 3. <programming> \{API\} Definition Language.
\par 
\par \tab A project for Automatic Interface Test Generation.
\par 
\par \tab (1995-11-17)
\par 
\par AdLog
\par 
\par \tab <language> A language which adds a \{Prolog\} layer to \{Ada\}.
\par 
\par \tab ["AdLog, An Ada Components Set to Add Logic to Ada",
\par \tab G. Pitette, Proc Ada-Europe Intl Conf Munich, June 1988].
\par 
\par \tab (1995-03-21)
\par 
\par ADM
\par 
\par \tab <language> A picture \{query language\}, extension of \{Sequel2\}.
\par 
\par \tab ["An Image-Oriented Database System", Y. Takao et al, in
\par \tab Database Techniques for Pictorial Applications, A. Blaser ed,
\par \tab pp. 527-538].
\par 
\par \tab (1995-03-21)
\par 
\par ADMD
\par 
\par \tab\{Administration Management Domain\}
\par 
\par admin
\par 
\par \tab\{system administrator\}
\par 
\par Administration Management Domain
\par 
\par \tab <networking> (ADMD) An \{X.400\} \{Message Handling System\}
\par \tab\{public service carrier\}.  The ADMDs in all countries
\par \tab worldwide together provide the X.400 \{backbone\}.  Examples:
\par \tab\{MCImail\} and \{ATTmail\} in the U.S., \{British Telecom\}
\par \tab\{Gold400mail\} in the U.K.
\par 
\par \tab See also \{PRMD\}.
\par 
\par \tab [RFC 1208].
\par 
\par \tab (1997-05-07)
\par 
\par administrative distance
\par 
\par \tab <networking> A rating of the trustworthiness of a \{routing\}
\par \tab information source set by the router administrator.  In
\par \tab\{Cisco\} \{routers\}, administrative distance is a number between
\par \tab 0 and 255 (the higher the value, the less trustworthy the
\par \tab source).
\par 
\par \tab (1998-03-10)
\par 
\par Administrative Domain
\par 
\par \tab <networking> (AD) A collection of \{host\}s and \{router\}s, and
\par \tab the interconnecting network(s), managed by a single
\par \tab administrative authority.
\par 
\par \tab (1994-11-24)
\par 
\par admissible
\par 
\par \tab <algorithm> A description of a \{search algorithm\} that is
\par \tab guaranteed to find a minimal solution path before any other
\par \tab solution paths, if a solution exists.  An example of an
\par \tab admissible search algorithm is \{A* search\}.
\par 
\par \tab (1999-07-19)
\par 
\par Adobe Systems, Inc.
\par 
\par \tab <company> A California \{font\} foundry and \{software\} house.
\par \tab Adobe created the \{PostScript\} \{page description language\} and
\par \tab wrote the \{Blue Book\}, \{Green Book\}, \{Red Book\} and \{White
\par \tab Book\} on it.  They also developed \{PDF\}.  Adobe took over
\par \tab\{Frame Technology Corporation\} in late 1995/early 1996.
\par 
\par \tab\{Home (http://www.adobe.com/)\}.
\par 
\par \tab E-mail: <postmaster@adobe.com>.
\par 
\par \tab Address: Silicon Valley, California, USA.
\par 
\par \tab (1996-12-13)
\par 
\par Adobe Type Manager
\par 
\par \tab <text, tool, product> (ATM) Software that produces
\par \tab\{PostScript\} \{outline fonts\} on screen and paper.  There are
\par \tab versions that run under \{Microsoft Windows\} and on the
\par \tab\{Macintosh\}.  ATM can do \{hinting\}, \{multiple master\} and
\par \tab\{anti-aliasing\}.
\par 
\par \tab (1998-03-10)
\par 
\par ADPCM
\par 
\par \tab\{Adaptive Digital Pulse Code Modulation\}
\par 
\par ADR
\par 
\par \tab\{Astra Digital Radio\}
\par 
\par ADS
\par 
\par \tab An \{expert system\}.
\par 
\par ADSL
\par 
\par \tab\{Asymmetric Digital Subscriber Line\}
\par 
\par ADSP
\par 
\par \tab\{AppleTalk Data Stream Protocol\}
\par 
\par ADSU
\par 
\par \tab\{ATM Data Service Unit\}
\par 
\par ADT
\par 
\par \tab\{abstract data type\}
\par 
\par Advanced Audio Coding
\par 
\par \tab <audio> (AAC) A successor to \{MP3\}, allowing lower \{bit rates\}
\par \tab and more stable quality.
\par 
\par \tab See \{MPEG-2 AAC Low Profile\} and \{MPEG-4 AAC Main Profile\}.
\par 
\par \tab (2001-12-02)
\par 
\par Advanced Communication Function/Network Control Program
\par 
\par \tab <networking> (ACF/NCP, usually called just "NCP") The primary
\par \tab\{SNA\} \{network control program\}, one of the \{ACF\} products.
\par \tab ACF/NCP resides in the \{communications controller\} and
\par \tab interfaces with \{ACF/VTAM\} in the \{host processor\} to control
\par \tab network communications.
\par 
\par \tab NCP can also communicate with multiple hosts using local
\par \tab channel or remote links (\{PU\} type 5 or PU type 4) thus
\par \tab enabling cross domain application communication.  In a
\par \tab multiple \{mainframe\} SNA environment, any terminal or
\par \tab application can access any other application on any host using
\par \tab cross domain logon.
\par 
\par \tab See also \{Emulator program\}.
\par 
\par \tab [Communication or Communications?]
\par 
\par \tab (1999-01-29)
\par 
\par Advanced Communications Function
\par 
\par \tab <networking> (ACF) A group of \{IBM\} \{SNA\} products that
\par \tab provide \{distributed processing\} and resource sharing such as
\par \tab\{VTAM\} and \{NCP\}.
\par 
\par \tab [Communication or Communications?]
\par 
\par \tab (1997-05-07)
\par 
\par Advanced Computing Environment
\par 
\par \tab <body> (ACE) A consortium to agree on an \{open\} architecture
\par \tab based on the \{MIPS R4000\} chip.  A computer architecture ARCS
\par \tab will be defined, on which either \{OS/2\} or \{Open Desktop\} can
\par \tab be run.
\par 
\par \tab (1995-02-03)
\par 
\par Advanced Configuration and Power Interface
\par 
\par \tab <hardware, standard> (ACPI) An open industry standard
\par \tab developed by \{Intel\}, \{Microsoft\}, and \{Toshiba\} for
\par \tab configuration and \{power management\}.
\par 
\par \tab The key element of the standard is power management with two
\par \tab important improvements.  First, it puts the \{OS\} in control of
\par \tab power management.  In the currently existing \{APM\} model most
\par \tab of the power management tasks are run by the \{BIOS\}, with
\par \tab limited intervention from the OS.  In ACPI, the BIOS is
\par \tab responsible for the dirty details of communicating with
\par \tab hardware equipment but the control is in the OS.
\par 
\par \tab The other important feature is bringing power management
\par \tab features now available in \{portable computers\} only to the
\par \tab desktop as well as into servers.  Extremely low consumption
\par \tab states, i.e., in which only memory, or not even memory is
\par \tab powered, but from which ordinary interrupts (real time clock,
\par \tab keyboard, modem, etc.) can quickly wake the system, are today
\par \tab available in portables only.  The standard should make these
\par \tab available for a wider range of systems.
\par 
\par \tab For ACPI to work the operating system, the \{motherboard\}
\par \tab chipset, and for some functions even the \{CPU\} has to be
\par \tab designed for it.  Microsoft is heavily driving a move toward
\par \tab ACPI, both \{Windows NT 5.0\} and \{Windows 98\} will support it.
\par \tab It remains to be seen how much hardware manufacturers will
\par \tab embrace the technology and whether other operating system
\par \tab vendors will support it.
\par 
\par \tab\{ACPI Information Page (http://www.teleport.com/~acpi/)\}.
\par 
\par \tab (1998-03-27)
\par 
\par Advanced Data Communications Control Protocol
\par 
\par \tab <protocol> An \{ANSI\} \{standard\} \{bit-oriented\} \{data link\}
\par \tab control \{protocol\}.
\par 
\par \tab (1997-05-07)
\par 
\par Advanced Encryption Standard
\par 
\par \tab <cryptography, algorithm> (AES, Rijndael) The \{symmetric block
\par \tab cipher\}, designed by Joan Daemen and Vincent Rijmen, that won
\par \tab the \{NIST\}'s contest for a replacement for the \{Data
\par \tab Encryption Standard\} (DES).
\par \tab 
\par \tab Final, official acceptance as a Federal Information Processing
\par \tab Standard (FIPS) is expected some time between April and June
\par \tab 2001.
\par \tab 
\par \tab AES currently supports 128, 192 and 256-bit keys and
\par \tab encryption blocks, but may be extended in multiples of 32
\par \tab bits.
\par \tab 
\par \tab\{Home (http://www.nist.gov/aes)\}.
\par 
\par \tab\{Rijndael home page
\par \tab (http://www.esat.kuleuven.ac.be/~rijmen/rijndael/)\}.
\par 
\par \tab (2001-05-09)
\par 
\par Advanced Function Presentation
\par 
\par \tab <printer, language> (AFP) A \{page description language\} from
\par \tab\{IBM\} introduced in 1984 initially as Advanced Function
\par \tab Printing.  AFP was first developed for \{mainframes\} and then
\par \tab brought to \{minicomputers\} and \{workstations\}.  It is
\par \tab implemented on the various \{platforms\} by \{Print Services
\par \tab Facility\} (PSF) software, which generates the \{native\} IBM
\par \tab printer language, \{IPDS\} and, depending on the version,
\par \tab\{PostScript\} and LaserJet \{PCL\} as well.  IBM calls AFP a
\par \tab "printer architecture" rather than a page description
\par \tab language.
\par 
\par Advanced Function Printing
\par 
\par \tab\{Advanced Function Presentation\}
\par 
\par Advanced Intelligent Tape
\par 
\par \tab <storage> (AIT) A form of \{magnetic tape\} and drive using
\par \tab\{AME\} developed by \{Sony\} for storing large amounts of data.
\par \tab An AIT can store over 50 \{gigabytes\} and transfer data at six
\par \tab megabytes/second (in February 1999).  AIT features high speed
\par \tab file access, long head and media life, the \{ALDC compression\}
\par \tab\{algorithm\}, and a \{MIC\} chip.
\par 
\par \tab\{Home (http://www.aittape.com/)\}.
\par 
\par \tab\{Seagate
\par \tab (http://www.seagate.com/support/tape/scsiide/sidewinder/ait_main_page.shtml)\}.
\par 
\par \tab (1999-04-16)
\par 
\par Advanced Interactive eXecutive
\par 
\par \tab <operating system> (AIX) \{IBM\}'s version of \{Unix\}, taken as
\par \tab the basis for the \{OSF\} \{standard\}.
\par 
\par \tab\{Usenet\} newsgroup: \{news:comp.sys.unix.aix\}.
\par 
\par \tab (1994-11-24)
\par 
\par Advanced Micro Devices, Inc.
\par 
\par \tab <company> (AMD) A US manufacturer of \{integrated circuits\},
\par \tab founded in 1969.  AMD was the fifth-largest IC manufacturer in
\par \tab 1995.  AMD focuses on the personal and networked computation
\par \tab and communications market.  They produce \{microprocessors\},
\par \tab\{embedded processors\} and related peripherals, memories,
\par \tab\{programmable logic devices\}, circuits for telecommunications
\par \tab and networking applications.
\par 
\par \tab In 1995, AMD had 12000 employees in the USA and elsewhere and
\par \tab manufacturing facilities in Austin, Texas; Aizu-Wakamatsu,
\par \tab Japan; Bangkok, Thailand; Penang, Malaysia; and Singapore.
\par 
\par \tab AMD made the \{AMD 2900\} series of \{bit-slice\} \{TTL\} components
\par \tab and clones of the \{Intel 80386\} and \{Intel 486\}
\par \tab\{microprocessors\}.
\par 
\par \tab\{AMD Home (http://www.amd.com/)\}
\par 
\par \tab Address: Sunnyvale, CA, USA.
\par 
\par \tab (1995-02-27)
\par 
\par Advanced Network Systems Architecture
\par 
\par \tab <networking> (ANSA) A "\{software bus\}" based on a model for
\par \tab distributed systems developed as an \{ESPRIT\} project.
\par 
\par \tab\{Home (http://www.ansa.co.uk/)\}
\par 
\par \tab (1996-04-01)
\par 
\par Advanced Peer-to-Peer Networking
\par 
\par \tab <networking, product> (APPN) IBM data communications support
\par \tab that routes data in a network between two or more \{APPC\}
\par \tab systems that need not be adjacent.
\par 
\par \tab (1995-02-03)
\par 
\par Advanced Power Management
\par 
\par \tab <hardware> (APM) A feature of some displays, usually but not
\par \tab always, on \{laptop computers\}, which turns off power to the
\par \tab display after a preset period of inactivity to conserve
\par \tab electrical power.  Monitors with this capability are usually
\par \tab refered to as "green monitors", meaning environmentally
\par \tab friendly.
\par 
\par \tab Not to be confused with a \{screen blanker\} which is \{software\}
\par \tab that causes the display to go black (by setting every \{pixel\}
\par \tab to black) to prevent \{burn-in\}.
\par 
\par \tab (1997-08-25)
\par 
\par Advanced Program-to-Program Communications
\par 
\par \tab <networking, product> (APPC) An implementation of the \{IBM\}
\par \tab\{SNA\}/\{SDLC\} \{LU6.2\} \{protocol\} that allows interconnected
\par \tab systems to communicate and share the processing of programs.
\par 
\par \tab (1995-02-03)
\par 
\par Advanced Research Projects Agency
\par 
\par \tab\{Defense Advanced Research Projects Agency\}
\par 
\par Advanced Research Projects Agency Network
\par 
\par \tab <networking> (ARPANET) A pioneering longhaul \{wide area
\par \tab network\} funded by \{DARPA\} (when it was still called "ARPA"?).
\par \tab It became operational in 1968 and served as the basis for
\par \tab early networking research, as well as a central \{backbone\}
\par \tab during the development of the \{Internet\}.  The ARPANET
\par \tab consisted of individual \{packet switching\} computers
\par \tab interconnected by \{leased lines\}.  \{Protocols\} used include
\par \tab\{FTP\} and \{telnet\}.  It has now been replaced by \{NSFnet\}.
\par 
\par \tab [1968 or 1969?]
\par 
\par \tab (1994-11-17)
\par 
\par Advanced Revelation
\par 
\par \tab <database> (AREV) A \{database development environment\} for
\par \tab\{personal computers\} available from \{Revelation Software\}
\par \tab since 1982.  Originally based on the \{PICK\} \{operating
\par \tab system\}, there are over one million users worldwide in 1996.
\par 
\par \tab (1996-12-12)
\par 
\par Advanced RISC Computing Specification
\par 
\par \tab <standard, hardware> (ARC, previously ARCS) The baseline
\par \tab hardware requirements for an \{ACE\}-compatible system.
\par 
\par \tab (1995-01-16)
\par 
\par Advanced RISC Machine
\par 
\par \tab <processor> (ARM, Originally \{Acorn\} RISC Machine).  A series
\par \tab of low-cost, power-efficient 32-bit \{RISC\} \{microprocessors\}
\par \tab for embedded control, computing, \{digital signal processing\},
\par \tab\{games\}, consumer \{multimedia\} and portable applications.  It
\par \tab was the first commercial RISC microprocessor (or was the \{MIPS
\par \tab R2000\}?) and was licensed for production by \{Asahi Kasei
\par \tab Microsystems\}, \{Cirrus Logic\}, \{GEC Plessey Semiconductors\},
\par \tab\{Samsung\}, \{Sharp\}, \{Texas Instruments\} and \{VLSI Technology\}.
\par 
\par \tab The ARM has a small and highly \{orthogonal\} \{instruction set\},
\par \tab as do most RISC processors.  Every instruction includes a
\par \tab four-bit code which specifies a condition (of the \{processor
\par \tab status register\}) which must be satisfied for the instruction
\par \tab to be executed.  Unconditional execution is specified with a
\par \tab condition "true".
\par 
\par \tab Instructions are split into load and store which access memory
\par \tab and arithmetic and logic instructions which work on
\par \tab\{registers\} (two source and one destination).
\par 
\par \tab The ARM has 27 registers of which 16 are accessible in any
\par \tab particular processor mode.  R15 combines the \{program counter\}
\par \tab and processor status byte, the other registers are general
\par \tab purpose except that R14 holds the \{return address\} after a
\par \tab\{subroutine\} call and R13 is conventionally used as a \{stack
\par \tab pointer\}.  There are four processor modes: user, \{interrupt\}
\par \tab (with a private copy of R13 and R14), fast interrupt (private
\par \tab copies of R8 to R14) and \{supervisor\} (private copies of R13
\par \tab and R14).  The \{ALU\} includes a 32-bit \{barrel-shifter\}
\par \tab allowing, e.g., a single-\{cycle\} shift and add.
\par 
\par \tab The first ARM processor, the ARM1 was a prototype which was
\par \tab never released.  The ARM2 was originally called the Acorn RISC
\par \tab Machine.  It was designed by \{Acorn Computers Ltd.\} and used
\par \tab in the original \{Archimedes\}, their successor to the \{BBC
\par \tab Micro\} and \{BBC Master\} series which were based on the
\par \tab eight-bit \{6502\} \{microprocessor\}.  It was clocked at 8 MHz
\par \tab giving an average performance of 4 - 4.7 \{MIPS\}.  Development
\par \tab of the ARM family was then continued by a new company,
\par \tab\{Advanced RISC Machines Ltd.\}
\par 
\par \tab The \{ARM3\} added a \{fully-associative\} on-chip \{cache\} and
\par \tab some support for \{multiprocessing\}.  This was followed by the
\par \tab\{ARM600\} chip which was an \{ARM6\} processor \{core\} with a
\par \tab 4-kilobyte 64-way \{set-associative\} \{cache\}, an \{MMU\} based on
\par \tab the MEMC2 chip, a \{write buffer\} (8 words?) and a
\par \tab\{coprocessor\} interface.
\par 
\par \tab The \{ARM7\} processor core uses half the power of the \{ARM6\}
\par \tab and takes around half the \{die\} size.  In a full processor
\par \tab design (\{ARM700\} chip) it should provide 50% to 100% more
\par \tab performance.
\par 
\par \tab In July 1994 \{VLSI Technology, Inc.\} released the \{ARM710\}
\par \tab processor chip.
\par 
\par \tab\{Thumb\} is an implementation with reduced code size
\par \tab requirements, intended for \{embedded\} applications.
\par 
\par \tab An \{ARM800\} chip is also planned.
\par 
\par \tab\{AT&T\}, \{IBM\}, \{Panasonic\}, \{Apple Coputer\}, \{Matsushita\} and
\par \tab\{Sanyo\} either rely on, or manufacture, ARM 32-bit processor
\par \tab chips.
\par 
\par \tab\{Usenet\} newsgroup: \{news:comp.sys.arm\}.
\par 
\par \tab (1997-08-05)
\par 
\par Advanced RISC Machines Ltd.
\par 
\par \tab <company> (ARM) A company formed in 1990 by \{Acorn Computers\}
\par \tab Ltd., \{Apple Computer, Inc.\} and \{VLSI Technology\} to market
\par \tab and develop the \{Advanced RISC Machine\} \{microprocessor\}
\par \tab family, originally designed by Acorn.
\par 
\par \tab ARM Ltd. also designs and licenses peripheral chips and
\par \tab supplies supporting software and hardware tools.  In April
\par \tab 1993, Nippon Investment and Finance, a Daiwa Securities
\par \tab company, became ARM's fourth investor.  In May 1994 Samsung
\par \tab became the sixth large company to have a licence to use the
\par \tab ARM processor core.
\par 
\par \tab The success of ARM Ltd. and the strategy to widen the
\par \tab availability of RISC technology has resulted in its chips now
\par \tab being used in a range of products including the \{Apple
\par \tab Newton\}.  As measured by an independent authority, more ARM
\par \tab processors were shipped than \{SPARC\} chips in 1993.  ARM has
\par \tab also sold three times more chips than the \{PowerPC\}
\par \tab consortium.
\par 
\par \tab\{Home (http://www.systemv.com/armltd/index.html)\}
\par 
\par \tab E-mail: armltd.co.uk.
\par 
\par \tab Address: Advanced RISC Machines Ltd.  Fulbourn Road, Cherry
\par \tab Hinton, Cambridge CB1 4JN, UK.
\par 
\par \tab Telephone: +44 (1223) 400 400.  Fax: +44 (1223) 400 410.
\par 
\par \tab (1994-11-03)
\par 
\par Advanced SCSI Peripheral Interface
\par 
\par \tab <storage, programming> (ASPI) A set of libraries designed to
\par \tab provide programs running under \{Microsoft Windows\} with a
\par \tab consistent interface for accessing \{SCSI\} devices.  ASPI has
\par \tab become a \{de facto standard\}.
\par 
\par \tab The ASPI layer is a collection of programs (\{DLL\}s) that
\par \tab together implement the ASPI interface.  Many problems are
\par \tab caused by device manufacturers packaging incomplete sets of
\par \tab these DLLs with their hardware, often with incorrect date
\par \tab stamps, causing newer versions to get replaced with old.
\par \tab ASPICHK from Adaptec will check the ASPI components installed
\par \tab on a computer.
\par 
\par \tab The latest ASPI layer as of March 1999 is 1014.
\par 
\par \tab The \{ATAPI\} standard for \{IDE\} devices makes them look to the
\par \tab system like SCSI devices and allows them to work through ASPI.
\par 
\par \tab\{(http://resource.simplenet.com/primer/aspi.htm)\}.
\par 
\par \tab (1999-03-30)
\par 
\par Advanced Software Environment
\par 
\par \tab <programming> (ASE) An \{object-oriented\} \{application support
\par \tab system\} from \{Nixdorf\}.
\par 
\par \tab (1995-09-12)
\par 
\par Advanced STatistical Analysis Program
\par 
\par \tab <tool, electronics> (ASTAP) A program for analysing electronic
\par \tab circuits and other networks.
\par 
\par \tab ["Advanced Statistical Analysis Program (ASTAP) Program
\par \tab Reference Manual", SH-20-1118, IBM, 1973].
\par 
\par \tab (2000-01-27)
\par 
\par Advanced Technology Attachment
\par 
\par \tab <storage, hardware, standard> (ATA, AT Attachment or
\par \tab "Integrated Drive Electronics", IDE) A \{disk drive\} interface
\par \tab\{standard\} based on the \{IBM PC\} \{ISA\} 16-bit \{bus\} but also
\par \tab used on other \{personal computers\}.  The ATA specification
\par \tab deals with the power and data signal interfaces between the
\par \tab\{motherboard\} and the integrated \{disk controller\} and drive.
\par \tab The ATA "bus" only supports two devices - master and slave.
\par 
\par \tab ATA drives may in fact use any physical interface the
\par \tab manufacturer desires, so long as an embedded translator is
\par \tab included with the proper ATA interface.  ATA "controllers" are
\par \tab actually direct connections to the ISA bus.
\par 
\par \tab Originally called IDE, the ATA interface was invented by
\par \tab\{Compaq\} around 1986, and was developed with the help of
\par \tab\{Western Digital\}, \{Imprimis\}, and then-upstart \{Conner
\par \tab Peripherals\}.  Efforts to standardise the interface started in
\par \tab 1988; the first draft appeared in March 1989, and a finished
\par \tab version was sent to \{ANSI\} group X3T10 (who named it "Advanced
\par \tab Technology Attachment" (ATA)) for ratification in November
\par \tab 1990.
\par 
\par \tab X3T10 later extended ATA to \{Advanced Technology Attachment
\par \tab Interface with Extensions\} (ATA-2), followed by \{ATA-3\} and
\par \tab\{ATA-4\}.
\par 
\par \tab\{X3T10 (http://www.symbios.com/x3t10/)\}.
\par 
\par \tab (1998-10-08)
\par 
\par Advanced Technology Attachment Interface with Extensions
\par 
\par \tab <storage, standard> (ATA-2, Enhanced Integrated Drive
\par \tab Electronics, EIDE) A proposed (May 1996 or earlier?)
\par \tab\{standard\} from \{X3T10\} (document 948D rev 3) which extends
\par \tab the \{Advanced Technology Attachment\} interface while
\par \tab maintaining compatibility with current \{IBM PC\} \{BIOS\}
\par \tab designs.
\par 
\par \tab ATA-2 provides for faster data rates, 32-bit transactions and
\par \tab (in some drives) \{DMA\}.  Optional support for power saving
\par \tab modes and removable devices is also in the standard.
\par 
\par \tab ATA-2 was developed by \{Western Digital\} as "Enhanced
\par \tab Integrated Drive Electronics" (EIDE) around 1994.
\par \tab\{Marketroids\} call it "Fast ATA" or "Fast ATA-2".
\par 
\par \tab ATA-2 was followed by \{ATA-3\} and \{ATA-4\} ("Ultra DMA").
\par 
\par \tab (2000-10-07)
\par 
\par Advanced WavEffect
\par 
\par \tab <multimedia, music, hardware> (AWE) The kind of synthesis used
\par \tab by the \{EMU 8000\} music synthesizer \{integrated circuit\} found
\par \tab on the \{SB AWE32\} card.
\par 
\par \tab (1996-12-15)
\par 
\par ADVENT
\par 
\par \tab <games> /ad'vent/ The prototypical computer \{Adventure\} game,
\par \tab first implemented by Will Crowther for a \{CDC\} computer
\par \tab (probably the 6600?) as an attempt at computer-refereed
\par \tab fantasy gaming.
\par 
\par \tab ADVENT was ported to the \{PDP-10\}, and expanded to the
\par \tab 350-point \{Classic\} puzzle-oriented version, by Don Woods of
\par \tab the \{Stanford Artificial Intelligence Laboratory\} (SAIL).  The
\par \tab game is now better known as Adventure, but the \{TOPS-10\}
\par \tab\{operating system\} permitted only six-letter filenames.  All
\par \tab the versions since are based on the SAIL port.
\par 
\par \tab David Long of the \{University of Chicago\} Graduate School of
\par \tab Business Computing Facility (which had two of the four
\par \tab\{DEC20\}s on campus in the late 1970s and early 1980s) was
\par \tab responsible for expanding the cave in a number of ways, and
\par \tab pushing the point count up to 500, then 501 points.  Most of
\par \tab his work was in the data files, but he made some changes to
\par \tab the \{parser\} as well.
\par 
\par \tab This game defined the terse, dryly humorous style now expected
\par \tab in text adventure games, and popularised several tag lines
\par \tab that have become fixtures of hacker-speak: "A huge green
\par \tab fierce snake bars the way!"  "I see no X here" (for some noun
\par \tab X).  "You are in a maze of twisty little passages, all alike."
\par \tab "You are in a little maze of twisty passages, all different."
\par \tab The "magic words" \{xyzzy\} and \{plugh\} also derive from this
\par \tab game.
\par 
\par \tab Crowther, by the way, participated in the exploration of the
\par \tab Mammoth & Flint Ridge cave system; it actually *has* a
\par \tab "Colossal Cave" and a "Bedquilt" as in the game, and the "Y2"
\par \tab that also turns up is cavers' jargon for a map reference to a
\par \tab secondary entrance.
\par 
\par \tab See also \{vadding\}.
\par 
\par \tab [Was the original written in Fortran?]
\par 
\par \tab [\{Jargon File\}]
\par 
\par \tab (1996-04-01)
\par 
\par Adventure Definition Language
\par 
\par \tab <language, games> (ADL) An \{adventure\} game language
\par \tab\{interpreter\} designed by Ross Cunniff <cunniff@fc.hp.com> and
\par \tab Tim Brengle in 1987.  ADL is semi-\{object-oriented\} with
\par \tab\{Lisp\}-like \{syntax\} and is a superset of \{DDL\}.  It is
\par \tab available for \{Unix\}, \{MS-DOS\}, \{Amiga\} and \{Acorn\}
\par \tab\{Archimedes\}.
\par 
\par \tab\{(ftp://ftp.uu.net/usenet/comp.sources.games/volume2)\},
\par \tab\{(ftp://ftp.wustl.edu/systems/amiga/fish/fish/f0/ff091)\}.
\par 
\par \tab (1995-03-20)
\par 
\par ADVSYS
\par 
\par \tab <language, games> An \{adventure\} game language designed by
\par \tab David Betz in 1986.  ADVSYS is \{object-oriented\} and
\par \tab\{Lisp\}-like.
\par 
\par \tab\{(ftp://ftp.uu.net/usenet/comp.sources.games/volume2)\}
\par 
\par \tab (1995-03-20)
\par 
\par AE
\par 
\par \tab\{Application Executive\}
\par 
\par ae
\par 
\par \tab <networking> The \{country code\} for the United Arab Emirates.
\par 
\par \tab (1999-01-27)
\par 
\par AED
\par 
\par \tab\{Automated Engineering Design\}
\par 
\par AEGIS
\par 
\par \tab <operating system> A \{Unix\} variant that was used on \{Apollo\}
\par \tab\{workstations\} before Apollo was bought by \{Hewlett Packard\}.
\par \tab AEGIS has some advantages over standard \{BSD\} or \{System V\}
\par \tab Unix.  It includes faster file access and a richer command
\par \tab set; there are commands to find out which \{process\} is running
\par \tab on a particular node, which process is locking a particular
\par \tab file, etc.
\par 
\par \tab (1997-02-25)
\par 
\par Aegis
\par 
\par \tab <programming, tool> A \{CASE\} tool for project change
\par \tab management, from the \{GNU\} project.
\par 
\par \tab (1995-03-27)
\par 
\par Aeolus
\par 
\par \tab <language> A \{concurrent\} language with \{atomic transaction\}s.
\par 
\par \tab ["Rationale for the Design of Aeolus", C. Wilkes et al, Proc
\par \tab IEEE 1986 Intl Conf Comp Lang, IEEE 1986, pp.107-122].
\par 
\par \tab (1995-03-27)
\par 
\par AEP
\par 
\par \tab\{Application Environment Profile\}
\par 
\par aeroplane rule
\par 
\par \tab <convention> "Complexity increases the possibility of failure;
\par \tab a twin-engine aeroplane has twice as many engine problems as a
\par \tab single-engine aeroplane."
\par 
\par \tab By analogy, in both software and electronics, the implication
\par \tab is that simplicity increases robustness and that the right way
\par \tab to build reliable systems is to put all your eggs in one
\par \tab basket, after making sure that you've built a really *good*
\par \tab basket.
\par 
\par \tab While simplicity is a useful design goal, and twin-engine
\par \tab aeroplanes do have twice as many engine problems, the analogy
\par \tab is almost entirely bogus.  Commercial passenger aircraft are
\par \tab required to have at least two engines (on different wings or
\par \tab nacelles) so that the aeroplane can land safely if one engine
\par \tab fails.  As Albert Einstein said, "Everything should be made as
\par \tab simple as possible, but not simpler".
\par 
\par \tab See also \{KISS Principle\}.
\par 
\par \tab (1999-03-22)
\par 
\par AES
\par 
\par \tab 1. <programming> \{Application environment specification\}.
\par 
\par \tab 2. <security> \{Advanced Encryption Standard\}.
\par 
\par \tab (1999-11-03)
\par 
\par AESOP
\par 
\par \tab\{An Evolutionary System for On-line Programming\}
\par 
\par af
\par 
\par \tab <networking> The \{country code\} for Afghanistan.
\par 
\par \tab (1999-01-27)
\par 
\par AFAC
\par 
\par \tab <language> An early system on the \{IBM 704\}.
\par 
\par \tab [Listed in CACM 2(5):16 (May 1959)].
\par 
\par \tab (1995-04-04)
\par 
\par AFAIK
\par 
\par \tab <chat> as far as I know.
\par 
\par affine transformation
\par 
\par \tab <mathematics> A \{linear transformation\} followed by a
\par \tab\{translation\}.  Given a \{matrix\} M and a \{vector\} v,
\par 
\par \tab   A(x) = Mx + v
\par 
\par \tab is a typical affine transformation.
\par 
\par \tab (1995-04-10)
\par 
\par affordance
\par 
\par \tab <graphics> A visual clue to the function of an object.
\par 
\par \tab (1998-10-15)
\par 
\par AFIPS
\par 
\par \tab\{American Federation of Information Processing Societies\}
\par 
\par AFJ
\par 
\par \tab\{April Fool's Joke\}
\par 
\par AFK
\par 
\par \tab <chat> away from keyboard.
\par 
\par aflex
\par 
\par \tab <tool> A \{Lex\}-like \{scanner generator\} that produce \{Ada\}
\par \tab output from IRUS (Irvine Research Unit in Software).  aflex
\par \tab comes with \{ayacc\}.
\par 
\par \tab Version 1.2a.
\par 
\par \tab Mailing list: <irus-software-request@ics.uci.edu>.
\par 
\par \tab\{(ftp://liege.ics.uci.edu/pub/irus/aflex-ayacc_1.2a.tar.Z)\}
\par 
\par \tab (1993-01-06)
\par 
\par AFNOR
\par 
\par \tab <body, standard> Association Francaise pour la Normalisation.
\par 
\par \tab The French national \{standard\}s institute, a member of \{ISO\}.
\par 
\par \tab (1994-12-14)
\par 
\par AFP
\par 
\par \tab 1. <protocol> \{Appletalk Filing Protocol\}.
\par 
\par \tab 2. <printer, language> \{Advanced Function Presentation\}.
\par 
\par \tab (1998-06-28)
\par 
\par AFS
\par 
\par \tab\{Andrew File System\}
\par 
\par AFUU
\par 
\par \tab\{Association Fran\'e7aise des Utilisateurs d'Unix\}
\par 
\par ag
\par 
\par \tab <networking> The \{country code\} for Antigua and Barbuda.
\par 
\par \tab (1999-01-27)
\par 
\par agent
\par 
\par \tab <networking> In the \{client-server\} model, the part of the
\par \tab system that performs information preparation and exchange on
\par \tab behalf of a \{client\} or \{server\}.  Especially in the phrase
\par \tab "intelligent agent" it implies some kind of automatic process
\par \tab which can communicate with other agents to perform some
\par \tab collective task on behalf of one or more humans.
\par 
\par \tab (1995-04-09)
\par 
\par aggregate type
\par 
\par \tab <programming> A data \{type\} composed of multiple elements.  An
\par \tab aggregate can be homogeneous (all elements have the same type)
\par \tab e.g. an \{array\}, a list in a \{functional language\}, a string
\par \tab of characters, a file; or it can be heterogeneous (elements
\par \tab can have different types) e.g. a \{structure\}.  In most
\par \tab languages aggregates can contain elements which are themselves
\par \tab aggregates. e.g. a list of lists.
\par 
\par \tab See also \{union\}.
\par 
\par \tab (1996-03-23)
\par 
\par aggregation
\par 
\par \tab <programming> A composition technique for building a new
\par \tab\{object\} from one or more existing objects that support some
\par \tab or all of the new object's required interfaces.
\par 
\par \tab (1996-01-07)
\par 
\par AGL
\par 
\par \tab <programming> (Atelier de Genie Logiciel) French for \{IPSE\}.
\par 
\par \tab (1997-01-07)
\par 
\par AGM Theory for Belief Revision
\par 
\par \tab <artificial intelligence> (After the initials of the authors
\par \tab who established the field - Alchourron, Makinson and
\par \tab Gardenfors).  A method of \{belief revision\} giving minimal
\par \tab properties a revision process should have.
\par 
\par \tab [Reference?]
\par 
\par \tab (1995-03-20)
\par 
\par AGORA
\par 
\par \tab <language> A distributed \{object-oriented language\}.
\par 
\par AGP
\par 
\par \tab\{Accelerated Graphics Port\}
\par 
\par AGP graphics
\par 
\par \tab\{Accelerated Graphics Port\}
\par 
\par A Hardware Programming Language
\par 
\par \tab <language> (AHPL) A \{register\}-level language by Hill and
\par \tab Peterson, some of whose operators resemble \{APL\}.
\par 
\par \tab HPSIM2 is a function-level simulator, available from Engrg
\par \tab Expt Sta, \{University of Arizona\}.
\par 
\par \tab ["Digital Systems: Hardware Organization and Design", F. Hill
\par \tab et al, Wiley 1987].
\par 
\par \tab (1995-01-26)
\par 
\par AHDL
\par 
\par \tab\{Analog Hardware Design Language\}
\par 
\par AHPL
\par 
\par \tab\{A Hardware Programming Language\}
\par 
\par AI
\par 
\par \tab\{artificial intelligence\}
\par 
\par ai
\par 
\par \tab <networking> The \{country code\} for Anguilla.
\par 
\par \tab (1999-01-27)
\par 
\par AIA
\par 
\par \tab\{Application Integration Architecture\}
\par 
\par AI-complete
\par 
\par \tab <artificial intelligence, jargon> /A-I k*m-pleet'/ (MIT,
\par \tab Stanford: by analogy with "\{NP-complete\}") A term used to
\par \tab describe problems or subproblems in \{artificial intelligence\},
\par \tab to indicate that the solution presupposes a solution to the
\par \tab "strong AI problem" (that is, the synthesis of a human-level
\par \tab intelligence).  A problem that is AI-complete is, in other
\par \tab words, just too hard.
\par 
\par 
\par }
 