`
`Apple 1022
`
`US. Pat. 8,724,622
`
`Apple 1022
`U.S. Pat. 8,724,622
`
`i
`
`

`

`PUBLISHED BY
`Microsoft Press
`A Division of Microsoft Corporation
`One Microsoft Way
`Redmond, Washington 98052-6399
`
`Copyright © 2002 by Microsoft Corporation
`
`All rights reserved. No part of the contents of this book may be reproduced or transmitted in any form
`or by any means without the written permission of the publisher.
`
`Library of Congress Cataloging-in-Publication Data
`Microsoft Computer Dictionary.--5th ed.
`p. cm.
`ISBN 0-7356-1495-4
`1. Computers--Dictionaries. 2. Microcomputers--Dictionaries.
`
`AQ76.5. M52267
`004'.03--dc21
`
`2002
`
`200219714
`
`Printed and bound in the United States of America.
`
`2 3 4 5 6 7 8 9 QWT
`
`7 6 5 4 3 2
`
`Distributed in Canada by H.B. Fenn and Company Ltd.
`
`A CIP catalogue record for this book is available from the British Library.
`
`Microsoft Press books are available through booksellers and distributors worldwide. For further informa-
`tion about international editions, contact your local Microsoft Corporation office or contact Microsoft
`Press International directly at fax (425) 936-7329. Visit our Web site at www.microsoft.com/mspress.
`Send comments to mspinput@microsoft.com.
`
`Active Desktop, Active Directory, ActiveMovie, ActiveStore, ActiveSync, ActiveX, Authenticode,
`BackOffice, BizTalk, ClearType, Direct3D, DirectAnimation, DirectDraw, DirectInput, DirectMusic,
`DirectPlay, DirectShow, DirectSound, DirectX, Entourage, FoxPro, FrontPage, Hotmail, IntelliEye,
`IntelliMouse, IntelliSense, JScript, MapPoint, Microsoft, Microsoft Press, Mobile Explorer, MS-DOS,
`MSN, Music Central, NetMeeting, Outlook, PhotoDraw, PowerPoint, SharePoint, UltimateTV, Visio,
`Visual Basic, Visual C++, Visual FoxPro, Visual InterDev, Visual J++, Visual SourceSafe, Visual Studio,
`Win32, Win32s, Windows, Windows Media, Windows NT, Xbox are either registered trademarks or
`trademarks of Microsoft Corporation in the United States and/or other countries. Other product and
`company names mentioned herein may be the trademarks of their respective owners.
`
`The example companies, organizations, products, domain names, e-mail addresses, logos, people, places,
`and events depicted herein are fictitious. No association with any real company, organization, product,
`domain name, e-mail address, logo, person, place, or event is intended or should be inferred.
`
`Acquisitions Editor: Alex Blanton
`Project Editor: Sandra Haynes
`
`Body Part No. X08-41929
`
`ii
`
`

`

`Contributors
`
`Peter Aiken
`
`Bart Arenson
`
`Janice Borzendowski
`
`Jerome Colburn
`
`Duane Hanson
`
`Andrew Himes
`
`Robert Howecton
`
`Annette B. Jackson
`
`Larry S. Jackson
`
`Thomas A. Jackson
`
`Chris Kinata
`
`Ilana Kingsley
`
`Robin Lombard
`
`Thomas A. Long
`
`William G. Madison
`
`Illustrators
`
`Travis Beaven
`
`David Holter
`
`Alton Lawson
`
`Thomas P. Magliery
`
`David Mason
`
`Terrence M. McLaren
`
`Wallace Parker
`
`Charles Petzold
`
`Phil Rose
`
`John Ross
`
`David Rygmyr
`
`Aimée Truchard
`
`Michael Vose
`
`Bruce Webster
`
`Judson D. Weeks
`
`Tom Winn
`
`JoAnne Woodcock
`
`Rob Nance
`
`Joel Panchot
`
`iii
`
`

`

`iv
`
`iv
`
`

`

`Contents
`
`Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
`Changes in the Fifth Edition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
`Order of Presentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
`Entries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
`Future Printings and Editions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
`
`Dictionary of Computer Terms . . . . . . . . . . . . . . . 1
`
`Appendix A:
`Common Character Sets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 587
`ANSI Character Set. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .587
`Apple Macintosh Extended Character Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .593
`IBM Extended Character Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .597
`EBCDIC Character Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .599
`Appendix B:
`Common File Extensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 605
`
`Appendix C:
`Instant Messaging Emoticons and Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 613
`
`Appendix D:
`Internet Domains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 623
`
`Appendix E:
`Numeric Equivalents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 631
`
`v
`
`

`

`Vi
`
`vi
`
`

`

`Introduction
`
`Introduction
`
`The Microsoft Computer Dictionary, Fifth Edition is
`designed to be a comprehensive and authoritative source of
`definitions for computer-related terms and abbreviations.
`The dictionary includes terms drawn from a wide variety
`of topics relevant to computer users, including software,
`hardware, networking, data storage, graphics, games,
`information processing, the Internet and the World Wide
`Web, gaming, history, jargon and slang, organizations, pro-
`gramming, and standards.
`Although this book covers nearly every aspect of comput-
`ing, it does not include entries on most companies or on
`most makes and models of computers, nor does it contain
`entries on most application software products. The few
`exceptions to this rule of thumb are key companies and
`products that have a historical or universal importance
`within the computing industry.
`This dictionary emphasizes terminology that the average
`computer user will encounter in documentation, online
`help, computer manuals, marketing and sales materials, the
`popular media, and the computer trade press. Because
`most computer users operate personal computers and desk-
`top systems at home, work, or both, the majority of the
`entries in this dictionary cover the terminology used in
`describing and working with these systems. However,
`some specialized or highly technical language is included
`that pertains to areas of industry, academia, software and
`hardware development, and research. These terms have
`been included because they have a bearing on more com-
`mon computer terminology or because they are of histori-
`cal significance.
`
`Changes in the Fifth Edition
`The fifth edition of the Microsoft Computer Dictionary has
`been revised and expanded to include over 10,000 entries,
`reflecting the many advances in the computer field and
`
`including several areas that have come into prominence in
`the public eye, such as networking, Web authoring, and
`new technologies, such as .NET. The content from the Year
`2000 appendix has been integrated into the body of the dic-
`tionary and a new appendix on emoticons and instant mes-
`saging symbols has been added.
`
`Order of Presentation
`Entries are alphabetized by letter. Spaces are ignored, as are
`characters such as hyphens and slashes; for example, Bau-
`dot code falls between baud and baud rate, and machine-
`independent falls between machine identification and
`machine instruction. Numbers and symbols are located at
`the beginning of the book and are listed in ascending ASCII
`order. If an entry begins with a letter or letters but contains
`a number, it is listed alphabetically, according to the initial
`letter(s), and then according to ASCII order. Thus, V20
`precedes V.2x, and both precede VAB.
`
`Entries
`Entries are of two types: main entries, which contain full
`definitions, and synonymous cross-references, which con-
`tain See references to the appropriate main entries. Synon-
`ymous cross-references are generally secondary or less
`common ways of referring to a main entry. The definition
`at the main entry can be substituted as a definition for the
`synonymous cross-reference.
`Format
`Information in each main entry is presented in a consistent
`format: entry name in boldface, spelling variants (if any),
`part of speech, definition, illustration or table reference (if
`any), acronym (if any), alternative names (if any), and
`cross-references (if any).
`
`vii
`
`

`

`Introduction
`
`Main Entries
`Entries that are acronyms or abbreviations for one or more
`words or concatenations of two or more words have those
`words spelled out at the beginning of the definition. The
`letters in these words or phrases that make up the acronym,
`abbreviation, or concatenation are in boldface.
`When a main entry is spelled exactly the same as another
`main entry, the two entries are differentiated by the use of a
`superscript numeral after each term. These entries are
`called homographs, and they are generally different parts
`of speech. For example,
`e-mail1 (noun)
`e-mail2 (verb)
`Spelling Variants
`When a main entry has one or more variations in the way it
`is spelled, each spelling variant follows the main entry,
`after the word or.
`Parts of Speech
`Entries are broken down into four parts of speech, in addi-
`tion to prefixes, abbreviated as follows:
`n. noun
`vb. verb
`adj. adjective
`adv. adverb
`Definitions
`Each of the more than 10,000 entries is written in clear,
`standard English. Many go beyond a simple definition to
`provide additional detail and to put the term in context for
`a typical computer user. When an entry has more than one
`sense or definition, the definitions are presented in a num-
`bered list, to make it easier to distinguish the particular,
`sometimes subtle, variations in meaning.
`Illustration and Table References
`Some entries have affiliated illustrations or tables that aid
`in defining the entry. In most cases, illustrations and tables
`appear on the same page as the entries to which they apply.
`
`In some instances, however, page layout requirements have
`forced them to a subsequent page. Entries with illustrations
`or tables usually have references at the end of the definition
`for an entry, in the following formats:
`See the illustration.
`See the table.
`Acronyms
`Some terminology in the computer field, particularly com-
`puter standards and Internet slang, can be shortened to
`form acronyms. Sometimes the acronym is the more com-
`mon way to refer to the concept or object; in these cases,
`the acronym is the main entry. In other cases, the acronym
`is not as commonly used as the words or phrase for which
`it stands. In these cases, the words or phrase constitute the
`main entry. The acronym is given after the definition for
`these entries in the following format:
`Acronym:
`Alternative Names
`Some items or concepts in the computer field can be
`referred to by more than one name. Generally, though, one
`way is preferred. The preferred terminology is the main
`entry. Alternative names are listed after any acronyms;
`otherwise they are listed after the definition in the follow-
`ing format:
`Also called:
`Cross-References
`Cross-references are of three types: See, See also, and Com-
`pare. A See reference is used in an entry that is a synony-
`mous cross-reference and simply points to another entry
`that contains the information sought. A See also reference
`points to one or more entries that contain additional or sup-
`plemental information about a topic and follows any acro-
`nyms or alternative names after the definition. A Compare
`reference points to an entry or entries that offer contrast and
`follows any See also references; otherwise it follows any
`acronyms or alternative names after the definition.
`
`viii
`
`

`

`Introduction
`
`Future Printings and Editions
`Every effort has been made to ensure the accuracy and
`completeness of this book. If you find an error, think that
`an entry does not contain enough information, or seek an
`entry that does not appear in this edition, please let us
`know. Address your letter to: Dictionary Editor, Microsoft
`Press, One Microsoft Way, Redmond, WA 98052-6399. Or
`send e-mail to mspcd@microsoft.com.
`
`ix
`
`

`

`x
`
`

`

`Numbers
`and Symbols
`
`#
`
`$0.02 n. See my two cents.
`& n. 1. UNIX command suffix for running the preceding
`command as a background process. See also background1.
`2. In UNIX, a root user command suffix for starting a
`daemon that is to remain running after logout. See also
`daemon. 3. The default character used to designate a char-
`acter entity (special character) in an HTML or SGML doc-
`ument. See also HTML, SGML. 4. In spreadsheet
`programs, an operator for inserting text into a formula
`specifying the relationship between cells.
`* n. 1. A character used in applications and programming
`languages to signify multiplication. 2. In Windows,
`MS-DOS, OS/2, and other operating systems, a wildcard
`character that can be used in place of one or more charac-
`ters, as in *.*, which represents any combination of a file-
`name and an extension. See also ?, *.*, wildcard character.
`3. In the C and C++ programming languages, the charac-
`ter used to dereference a pointer to a class or structure. See
`also dereference, pointer (definition 1).
`*.* n. A file specification using the asterisk (star) wild-
`card, which means any combination of filename and
`extension in operating systems such as MS-DOS. See also
`asterisk (definition 2), wildcard character.
`.. n. MS-DOS and UNIX syntax for the parent directory.
`A single dot refers to the current directory.
`/ n. 1. A character used to separate parts of a directory
`path in UNIX and FTP or parts of an Internet address
`(URL) in Web browsers. 2. A character used to flag
`switches or parameters that control the execution of a pro-
`gram invoked through a command-line interface. See also
`command-line interface.
`// n. Notation used with a colon to separate the URL pro-
`tocol (such as http or ftp) from the URL host machine
`name, as in http://www.yahoo.com. See also URL.
`: n. Colon, a symbol used after the protocol name (such as
`http or ftp) in a URL. See also URL.
`
`<> n. 1. Angle brackets, a pair of symbols used to enclose
`a keyword, comprising a tag in an HTML, SGML, or
`XML document. See also HTML, SGML, XML. 2. In an
`Internet Relay Chat (IRC) or multiuser dungeon (MUD), a
`set of symbols used to designate some action or reaction,
`as in <chuckle>. See also emotag, IRC, MUD. 3. A pair
`of symbols used to enclose a return address in an e-mail
`header.
`> n. 1. Right angle bracket, a symbol used in some operat-
`ing systems, such as MS-DOS and UNIX, to direct the
`output resulting from some command into a file. 2. A
`symbol commonly used in e-mail messages to designate
`text included from another message.
`? n. In some operating systems and applications, a wild-
`card character often used to represent any other single
`character. The question mark is one of two wildcard char-
`acters supported by the MS-DOS, Windows NT, and OS/2
`operating systems. See also *.
`@ n. The separator between account names and domain
`names in Internet e-mail addresses. When spoken, @ is
`read as “at.” Therefore, user@host.com would be read as
`“user at host dot com.”
`\ n. Back slash, a character used to separate directory
`names in MS-DOS and UNIX path specifications. When
`used as a leading character, it means that the path specifi-
`cation begins from the topmost level for that disk drive.
`See also path (definition 5).
`0.07-micron n. A manufacturing technology with which
`400 million transistors, with an effective channel length
`1000 times thinner than a human hair, can be placed on a
`single chip. The extremely small sizes and faster speeds of
`0.07-micron products can be used to create improved-per-
`formance microprocessors that may extend clock speeds
`beyond 10 GHz. Possible applications of 0.07-micron
`technology range from tiny hearing aids that can be
`implanted in the ear to hard disk drives that read gigabits
`of data per second.
`
`1
`
`

`

`#
`
`0 wait state
`
`0 wait state n. See zero wait state.
`100Base-FX n. An Ethernet standard for baseband LANs
`(local area networks) using fiber optic cable carrying 100
`Mbps (megabits per second). Also called: Fast Ethernet.
`See also Ethernet (definition 1).
`100Base-T n. An Ethernet standard for baseband LANs
`(local area networks) using twisted-pair cable carrying
`100 Mbps (megabits per second). The 100Base-T standard
`is comprised of 100Base-T4 (four pairs of medium-grade
`to high-grade twisted-pair cable) and 100Base-TX (two
`pairs of high-grade twisted-pair cable). Also called: Fast
`Ethernet. See also Ethernet (definition 1).
`100Base-T4 n. See 100Base-T.
`100Base-TX n. See 100Base-T.
`100Base-VG n. An Ethernet standard for baseband LANs
`(local area networks) using voice-grade twisted-pair cable
`carrying 100 Mbps (megabits per second). Unlike other
`Ethernet networks, 100Base-VG relies on an access
`method called demand priority, in which nodes send
`requests to hubs, which in turn give permission to transmit
`based on the priority levels included with the requests.
`Also called: 100Base-VG-AnyLAN. See also Ethernet
`(definition 1).
`100Base-VG-AnyLAN n. See 100Base-VG.
`100Base-X n. Descriptor used for any of three forms of
`100 Mbps Ethernet networks: 100Base-T4, 100Base-TX,
`or 100Base-FX. Also called: Fast Ethernet. See also
`100Base-T, 100Base-FX, Ethernet (definition 1).
`101-key keyboard n. A computer keyboard modeled
`after the enhanced keyboard; introduced by IBM for the
`IBM PC/AT. The 101-key keyboard and the enhanced key-
`board are similar in the number and function of their keys;
`they may differ in the way the keys are laid out, the
`amount of tactile feedback expressed when a key is
`pressed, and the shape and feel of the keycaps. See also
`enhanced keyboard.
`1024x768 n. A standard super VGA computer display
`having a resolution of 1024 columns of pixels by 768 rows
`of pixels. See also SVGA.
`10Base2 n. The Ethernet and IEEE 802.3 standard for
`baseband LANs (local area networks) using a thin coaxial
`cable (3/16 inch) up to 200 meters long and carrying 10
`Mbps (megabits per second) in a bus topology. A network
`node is connected to the cable by a BNC connector on the
`
`2
`
`16-bit
`
`adapter card. Also called: Cheapernet, thin Ethernet,
`ThinNet, ThinWire. See also BNC connector, bus net-
`work, coaxial cable, Ethernet (definition 1), IEEE 802.x.
`10Base5 n. The Ethernet and IEEE 802.3 standard for
`baseband LANs (local area networks) using a thick coaxial
`cable (3/8 inch) up to 500 meters long and carrying 10
`Mbps (megabits per second) in a bus topology. A network
`node is equipped with a transceiver that plugs into a 15-pin
`AUI connector on the adapter card and taps into the cable.
`This form of Ethernet is generally used for network back-
`bones. Also called: thick Ethernet, ThickNet, ThickWire.
`See also coaxial cable, Ethernet (definition 1), IEEE 802.x.
`10Base-F n. The Ethernet standard for baseband LANs
`(local area networks) using fiber-optic cable carrying 10
`Mbps (megabits per second) in a star topology. All nodes
`are connected to a repeater or to a central concentrator. A
`node is equipped with a fiber-optic transceiver that plugs
`into an AUI connector on the adapter card and attaches to
`the cable with an ST or SMA fiber-optic connector. The
`10Base-F standard comprises 10Base-FB for a backbone,
`10Base-FL for the link between the central concentrator
`and a station, and 10Base-FP for a star network. See also
`Ethernet (definition 1), fiber optics, star network.
`10Base-FB n. See 10Base-F.
`10Base-FL n. See 10Base-F.
`10Base-FP n. See 10Base-F.
`10Base-T n. The Ethernet standard for baseband LANs
`(local area networks) using twisted-pair cable carrying 10
`Mbps (megabits per second) in a star topology. All nodes
`are connected to a central hub known as a multiport
`repeater. See also Ethernet (definition 1), star network,
`twisted-pair cable.
`12-hour clock n. A clock that expresses the time within a
`12-hour range, returning to 1:00 after 12:59 AM or PM.
`Compare 24-hour clock.
`1.2M adj. Short for 1.2-megabyte. Refers to the storage
`capacity for high-density 5.25-inch floppy disks.
`1394 n. See IEEE 1394.
`14.4 n. A modem with a maximum data transfer rate of
`14.4 Kbps (kilobits per second).
`1.44M adj. Short for 1.44-megabyte. Refers to the stor-
`age capacity for high-density 3.5-inch floppy disks.
`16-bit adj. See 8-bit, 16-bit, 32-bit, 64-bit.
`
`

`

`#
`
`28.8
`
`1NF n. Short for first normal form. See normal form (def-
`inition 1).
`2000 time problem n. See Year 2000 problem.
`2038 limit n. A consideration in some PCs that use a
`signed 32-bit integer to represent date and time. Because
`such systems determine date and time as the number of
`seconds elapsed since midnight, January 1, 1970, they can
`handle a maximum of 231 seconds, a number that will be
`reached at 3:14:07 a.m. on January 19, 2038. When the
`elapsed seconds exceed that maximum value, the clock
`will overflow, resulting in an incorrect date and time and,
`potentially, causing disruptions. Some organizations have
`defined Year 2000 compliant to mean a system that will
`have the correct date/time and do proper date handling up
`through the year 2038, although this is not universal. The
`extent of the potential problem, of course, is directly
`related to the number of such system solutions still in
`operation at the time. See also Year 2000 compliant.
`24-bit color n. RGB color in which the level of each of
`the three primary colors in a pixel is represented by 8 bits
`of information. A 24-bit color image can contain over 16
`million different colors. Not all computer monitors sup-
`port 24-bit color, especially older models. Those that do
`not may use 8-bit color (256 colors) or 16-bit color
`(65,536 colors). Also called: true color. See also bit depth,
`pixel, RGB. Compare 16-bit color, 32-bit color.
`24-hour clock n. A clock that expresses the time within a
`24-hour range, from 0000 (midnight) to 2359 (one minute
`before the following midnight). Compare 12-hour clock.
`2.4 kernel n. Update of the core of the Linux OS, released
`at the end of 2000. Features in the 2.4 kernel emphasize
`support for new buses, devices, and controllers; increased
`USB support; improved Web server performance; and
`increased symmetrical multiprocessing scalability.
`/24 network n. IP address class A. This class has more
`than two million networks available and 254 hosts avail-
`able. See also host, IP address classes, network.
`256-bit adj. Having a data path that is 256 bits wide.
`286 n. See 80286.
`287 n. See 80287.
`28.8 n. A modem with a maximum data transfer rate of
`28.8 Kbps (kilobits per second).
`
`16-bit application
`
`16-bit application n. An application written to run on a
`computer with a 16-bit architecture or operating system,
`such as MS-DOS or Windows 3.x.
`16-bit color adj. Of, pertaining to, or characteristic of a
`display that can produce 216 (65,536) distinct colors. Com-
`pare 24-bit color, 32-bit color.
`16-bit machine n. A computer that works with data in
`groups of 16 bits at a time. A computer may be considered
`a 16-bit machine either because its microprocessor oper-
`ates internally on 16-bit words or because its data bus can
`transfer 16 bits at a time. The IBM PC/AT and similar
`models based on the Intel 80286 microprocessor are 16-bit
`machines in terms of both the word size of the micropro-
`cessor and the size of the data bus. The Apple Macintosh
`Plus and Macintosh SE use a microprocessor with a 32-bit
`word length (the Motorola 68000), but they have 16-bit
`data buses and are generally considered 16-bit machines.
`16-bit operating system n. An operating system, now
`outdated, that can work with 2 bytes, or 16 bits, of infor-
`mation at one time. A 16-bit operating system, such as
`MS-DOS and Microsoft Windows 3.x, reflects the func-
`tionality of a 16-bit processor because the software and
`the chip must work together so closely. The main advan-
`tage of a 16-bit operating system over its earlier 8-bit pre-
`decessors (such as CP/M-80) was its ability to address
`more memory and use a larger (16-bit) bus. Sixteen-bit
`operating systems have since been eclipsed by 32-bit oper-
`ating systems—such as the Macintosh operating system,
`Microsoft Windows NT, and Windows 9x—and by 64-bit
`operating systems, such as some versions of UNIX. See
`also 32-bit operating system.
`/16 network n. IP address class B. This class has 16,382
`networks available and more than sixty-five thousand
`hosts available. See also host, IP address classes, network.
`1999 problem n. 1. A variation on the Year 2000 prob-
`lem in computer systems that have two-digit years in date
`fields and are used by companies and organizations in
`which the fiscal year 2000 begins before the end of calen-
`dar year 1999. These computer systems may interpret the
`fiscal year as the year 1900. 2. A potential problem, if not
`corrected, with date fields in older code that were (some-
`times) used to hold values with special meaning. For
`example, the date 9/9/99 was often used as an expiration
`date meaning “keep this information forever” or, worse,
`“destroy this document immediately.”
`
`3
`
`

`

`#
`
`2-digit year
`
`2-digit year n. The capacity for storing only the last two
`digits of the year in a date. In such systems, the century for
`the date is not stored. See also two-digit date storage.
`2G n. Acronym for 2nd Generation. The second generation
`of digital wireless technology, as defined by the Interna-
`tional Telecommunications Union (ITU). Second generation
`technology delivers data transmission at speeds from 9.6
`Kbps (kilobits per second) to 19.2 Kbps. Second generation
`technology provides greater data transmission capabilities
`and more efficient voice transmission than the analog tech-
`nology first developed for wireless telecommunications.
`2NF n. Short for second normal form. See normal form
`(definition 1).
`2-nines availability n. See two-nines availability.
`2.PAK n. An artificial intelligence programming language.
`32-bit adj. See 8-bit, 16-bit, 32-bit, 64-bit.
`32-bit application n. An application written to run on a
`computer with a 32-bit architecture or operating system,
`such as Mac OS or Windows 9x.
`32-bit clean adj. 1. Refers to Macintosh hardware
`designed to run in 32-bit mode, which can address up to 1
`gigabyte of physical RAM under System 7. This includes
`all present Macintosh computers; some older models used
`16-bit addressing. 2. Refers to software written for 32-bit
`operation.
`32-bit color n. RGB color that is similar to 24-bit color,
`with 8 additional bits used to allow for faster transfer of an
`image's color. See also bit depth, RGB. Compare 16-bit
`color, 24-bit color.
`32-bit driver n. A software subsystem that controls either
`a hardware device (device driver) or another software sub-
`system. The 32-bit versions of this software take full
`advantage of the instruction sets of the 486 and Pentium
`processors for improved speed. See also driver, instruc-
`tion set.
`32-bit machine n. A computer that works with data in
`groups of 32 bits at a time. The Apple Macintosh II and
`higher models are 32-bit machines, in terms of both the
`word size of their microprocessors and the size of the data
`buses, as are computers based on the Intel 80386 and
`higher-level microprocessors.
`32-bit operating system n. An operating system in
`which 4 bytes, or 32 bits, can be processed at one time.
`
`4
`
`387SX
`
`Windows 95, Windows 98, Windows NT, Linux, and OS/2
`are examples. See also instruction set, protected mode.
`33.6 n. A modem with a maximum data transfer rate of
`33.3 Kbps (kilobits per second).
`34010, 34020 n. Graphics coprocessors from Texas
`Instruments (TI), used mainly in high-end PC graphics
`boards, which have become a de facto standard for pro-
`grammable graphics processors. Although both chips use
`32-bit registers, the 34010 uses a 16-bit data bus and the
`34020 uses a 32-bit bus. The 34020 is compatible with the
`earlier 34010, and both chips work with TIGA (Texas
`Instruments Graphical Architecture), a TI standard that
`allows a single application driver to be used with all
`boards based on the standard. See also de facto standard,
`TIGA, video graphics board.
`3.5-inch floppy disk n. Used with the Macintosh and
`with IBM and compatible microcomputers. A micro-
`floppy disk is a round piece of polyester film coated with
`ferric oxide and encased in a rigid plastic shell equipped
`with a sliding metal cover. On the Macintosh, a single-sided
`3.5-inch floppy disk can hold 400 kilobytes (KB); a
`double-sided (standard) disk can hold 800 KB; and a
`double-sided high-density disk can hold 1.44 megabytes
`(MB). On IBM and compatible machines, a microfloppy
`can hold either 720 KB or 1.44 MB of information. See
`also floppy disk.
`360K adj. Short for 360-kilobyte. The storage capacity
`for standard 5.25-inch floppy disks.
`.386 n. A file extension for virtual device drivers under
`Windows 3.1. See also virtual device driver.
`386 n. See 80386DX.
`386BSD n. A version of BSD UNIX, different from
`BSD386 from Berkeley Software Development, Inc.
`Freely distributable, 386BSD was released in 1992 and is
`available in two newer versions: NetBSD and FreeBSD.
`See also BSD UNIX, FreeBSD, NetBSD.
`386DX n. See 80386DX.
`386SL n. See 80386SL.
`386SX n. See 80386SX.
`387 n. See 80387.
`387SX n. See 80387SX.
`
`

`

`3-D
`
`3-D or 3D adj. 1. Short for three-dimensional. Of, per-
`taining to, or being an object or image having or appearing
`to have all three spatial dimensions (length, width, and
`depth). 2. Having the illusion of depth or varying dis-
`tances, as in 3-D audio.
`3-D array n. See three-dimensional array.
`3-D audio n. Short for three-dimensional audio.
`Recorded as stereo sound, 3-D audio enables the listener
`to feel immersed in the sound and to determine its exact
`location (up, down, left, right, forward, or backward). This
`technology is commonly used in video games and vir-
`tual-reality systems, as well as in some Internet applica-
`tions. Also called: 3-D sound, binaural sound.
`3-D graphic n. Any graphical image that depicts one or
`more objects in three dimensions—height, width, and
`depth. A 3-D graphic is rendered on a two-dimensional
`medium; the third dimension, depth, is indicated by means
`of perspective and by techniques such as shading or gradi-
`ent use of color.
`3-D metafile n. A device-independent file for storing a
`3-D display. See also metafile.
`3DMF n. See QuickDraw 3-D.
`3-D model n. See three-dimensional model.
`3-D sound n. See 3-D audio.
`3-finger salute n. See three-finger salute.
`3G n. Acronym for 3rd Generation. The third generation
`of digital wireless technology, as defined by the Interna-
`tional Telecommunications Union (ITU). Third generation
`technology is expected to deliver data transmission speeds
`between 144 Kbps (kilobits per second) and 2 Mbps
`(megabits per second), compared to the 9.6 Kbps to 19.2
`Kbps offered by second generation technology. Western
`Europe and Japan lead the world in adoption of 3G tech-
`nology and services.
`3GL n. Short for third-generation language. A high-level
`programming language that was designed to run on the
`third generation of computer processors, built on integrated
`circuit technology roughly from 1965 to 1970. C, FOR-
`TRAN, Basic, and Pascal are examples of third-generation
`languages still in use today. See also high-level language,
`integrated circuit. Compare 4GL, low-level language.
`3NF n. Short for third normal form. See normal form
`(definition 1).
`3-nines availability n. See three-nines availability.
`
`#
`
`4GL
`
`3Station n. A diskless workstation developed by Bob
`Metcalfe at 3Com Corporation. See also diskless work-
`station.
`400 n. HTTP status code—Bad Request. A Hypertext
`Transfer Protocol message from an HTTP server indicat-
`ing that a client request cannot be completed because the
`syntax of the request is incorrect. See also HTTP server
`(definition 1), HTTP status codes.
`401 n. HTTP status code—Unauthorized. A Hypertext
`Transfer Protocol message from an HTTP server indicating
`that a client request cannot be completed because the trans-
`action requires an Authorization header, which was not
`supplied. See also HTTP server (definition 1), HTTP sta-
`tus codes.
`402 n. HTTP status code—Payment Required. A Hyper-
`text Transfer Protocol message from an HTTP server indi-
`cating that a client request cannot be completed because
`the transaction requires a payment, and no ChargeTo
`header was supplied. See also HTTP server (definition 1),
`