Dictionary of
`Computer and
`Internet Terllls
`
`Eighth Edition
`
`Douglas A. Downing, Ph.D.
`School of Business and Economics
`Seattle Pacific University
`
`Michael A. Covington, Ph.D.
`Artificial Intelligence Center
`The University of Georgia
`
`Melody Mauldin Covington
`Covington Innovations
`Athens, Georgia
`
`With the assistance of
`Catherine Anne Covington
`
`1
`
`NVIDIA 1010
`
`

`

`ABOUT THE AUTHORS
`
`Douglas Downing teaches economics and quantitative methods and is undergrad(cid:173)
`uate program director for the School of Business and Economics at Seattle Pacific
`University. He is the author of several books in both Barron's Easy Way and Busi(cid:173)
`ness Review series. He is also the author of Java Programming the Easy Way and
`Dictionary of Mathematics Tenns, published by Barron's Educational Se1ies, Inc.
`He holds the Ph.D. degree in economics from Yale University.
`Michael Covington is Associate Director of the Artificial Intelligence Center at
`the University of Georgia. He is the author of several books and over 250 magazine
`articles. He holds the Ph.D. degree in linguistics from Yale University.
`Melody Mauldin Covington is a graphic designer living in Athens, Georgia. She
`is the author of Dictionary of Desktop Publishing (published by Barron's).
`Catherine Anne Covington is a student and web designer in Athens, Georgia.
`
`©Copyright 2003, 2000, 1998, 1996, 1995, 1992, 1989, and 1986
`by Barron's Educational Series, Inc.
`
`All rights reserved.
`No part of this book may be reproduced in any form, by photostat, microfilm,
`xerography, or any other means, or incorporated into any information
`retrieval system, electronic or mechanical, without the written permission
`of the copyright owner.
`
`All inquiries should be addressed to:
`Barron's Educational Series, Inc.
`250 Wireless Boulevard
`Hauppauge, New York 11788
`http ://www.barronseduc.com
`
`Library of Congress Catalog Card No. 2002033231
`
`International Standard Book No. 0-7641-2166-9
`
`Library of Congress Cataloging-in-Publication Data
`
`Downing, Douglas.
`Dictionary of computer and Internet terms I Douglas A. Downing,
`Michael A. Covington, Melody Mauldin Covington.-8th ed.
`p.
`cm.
`First-4th eds. published under title: Dictionary of computer terms.
`ISBN 0-7641-2166-9
`I. Covington,
`2. Internet Dictionaries.
`1. Computers-Dictionaries.
`II. Covington, Melody Mauldin.
`Michael A., 1957-
`III. Downing, Douglas.
`Dictionary of computer terms.
`IV. Title.
`
`QA76. I 5 .D667 2002
`0041 .03-dc2 l
`
`PRINTED IN THE UNITED STATES OF AMERICA
`
`987654321
`
`2002033231
`
`About the Auth
`
`To the Reader
`
`Dictionary of C
`Numbers
`Greek Le
`A
`B
`c
`D
`E .... ..
`F .... ..
`G .... ..
`H .... ..
`I ..... .
`J .... ..
`K ..... .
`L .... ..
`M ... ..
`N .... ..
`0 ..... .
`p .... ..
`Q .... ..
`R .... ..
`s ..... .
`T .... ..
`u .... ..
`v ..... .
`w ... ..
`x .... ..
`y
`z ......
`
`Visual Dictiom
`Country Codes
`
`2
`
`

`

`--------
`
`310
`
`UALITY
`
`aph
`hie print
`ortions of it will
`ed and enlarged
`photographs
`
`tpe, sometimes curable
`
`5netic disks, tapes, and
`
`uter user. Vision is one
`1g uses visible displays
`
`levision.
`
`of integrated circuits
`~GRATED CIRCUIT.
`
`·ating computer mem(cid:173)
`ld ega- is derived from
`!C PREFIXES.
`nory equal to 220 =
`te can store more than
`
`imes means the same
`~r, megabyte is used to
`1024 x 1000). These
`:erent numbers being
`ee also GIGABYTE.
`
`per second, a measure
`· of a radio signal. See
`
`e size of a graphical
`is often referred to as
`>ixels are needed for
`
`311
`
`menu
`
`various levels of image quality. See also DIGITAL CAMERA; PHOTOPAINT
`PROGRAM; EFFECTIVE MEGAPIXELS; GROSS MEGAPIXELS.
`meme virus an idea or belief that spreads quickly from person to
`person, like an infection, whether or not it is true; meme viruses do to
`the human mind what computer viruses do to software.
`End-of-the-world predictions, fads, and hoaxes are examples of
`meme viruses. Some people deliberately spread meme viruses on the
`Internet. See HOAX.
`The term meme was introduced by evolutionary biologist Richard
`Dawkins in 1976 to denote important ideas, skills, or habits that are
`passed along from person to person, almost like genes.
`memory (formerly called core) the space within a computer where
`information is stored while being actively worked on. Most microcom(cid:173)
`puters have a small amount of read-only memory (ROM), containing
`the built-in programs that start the operation of the computer when it
`is turned on, and a large amount of random-access memory (RAM) for
`user's programs and data. Except for ROM, memory goes blank when
`the computer is turned off; any data in it must be copied to disk or tape
`to be saved.
`See also EXPANDED MEMORY; EXTENDED MEMORY; MS-DOS; SIMM;
`DRAM; EDO; FPM; SDRAM; RDRAM.
`memory leak see LEAK.
`MemoryStick a type of flash-memory non-volatile storage device sim(cid:173)
`ilar to CompactFlash but physically long and thin, developed by Sony
`Corporation. Compare COMPACTFLASH; SMARTMEDIA; SECURE DIGITAL;
`MULTIMEDIACARD; FLASHCARD.
`Me.n.nphis Microsoft's internal code name for the Windows 98 devel(cid:173)
`opment project. See WINDOWS 98. Compare CHICAGO; CAIRO.
`menu a list of choices that appears on the screen in response to your
`actions. Most windows have a MENU BAR just under the title bar. When
`you click on an item in the menu bar, its corresponding menu will
`appear. You select the command you want by moving the mouse pointer
`to it. Commands with ellipsis dots( ... ) after them will pop up a dialog
`box for you to give the computer further instructions before executing
`the command. If there are keyboard shortcuts for any command, they
`will often be listed to the right of the command.
`Menus make a program user-friendly. It's very easy to learn and
`use software with a menu-driven command system. You don't need to
`memorize all the commands. By looking at the menus, you can see all
`the options.
`The problem with menus is that it often takes a substantial amount
`of time and mouse movement to work through them. Experienced users
`use the keyboard shortcuts to speed up their work. Also, if you are not
`careful, it is possible to get lost in a series of nested menus. Many
`
`3
`
`

`

`342
`
`343
`
`notebook
`
`J UNIX that enables com(cid:173)
`JFS was developed by Sun
`~rs from a wide variety of
`FILE SERVER.
`"
`
`1ard inside a computer that
`the first step in networking
`
`rechargeable battery often
`m batteries are toxic and
`ee also LI-ION.
`
`.-:hargeable battery electri-
`1t having greater capacity.
`
`another type of machine)
`
`::h as a linked list or tree.
`line that helps define the
`CUSP NODE.
`
`not indicate a place where
`he hyphenated word "flip(cid:173)
`" can appear on one line,
`fyou type "flip-flop" with
`Microsoft Word, to type a
`e hyphen key together.
`
`.ot denote a place where
`. For instance, you might
`") to be split at the end of
`:tees between them rather
`e is typed as - (TILDE). In
`1ed by pressing Ctrl-Shift
`
`;sing that produces plain(cid:173)
`yphenation, page breaks,
`saving a file in nondocu(cid:173)
`:;hoose "text file" or "text
`
`the entire screen in one
`
`non-volatile not erased when turned off. Disks are a non-volatile stor(cid:173)
`age medium; memory (RAM) is volatile.
`
`Inputs
`
`Output
`
`FIGURE 184. NOR gate (logic symbol)
`
`NOR gate (Figure 184) a logic gate whose output is 0 when either or
`both of the two inputs is 1, thus:
`
`Inputs
`0
`0
`0
`1
`1
`0
`1
`1
`
`Output
`1
`0
`0
`0
`
`A NOR gate is equivalent to an OR gate followed by a NOT gate. NOR
`gates are important because all the other types of logic circuits can be
`built from them. See LOGIC CIRCUITS.
`Norton Utilities a set of programs originally written by Peter Norton
`and now a product of Symantec Corporation, for Macintosh and PC(cid:173)
`compatible computers. Their most important function is to recover
`erased files and correct other problems with disks. See RECOVERING
`ERASED FILES.
`NOS
`1. (Network Operating System) any special operating system or oper(cid:173)
`ating system extension that supports networking. For an example, see
`NOVELL NETWARE.
`2. (New Old Stock) old but never sold to a customer and still in orig(cid:173)
`inal packaging; this describes parts for obsolete equipment or the like.
`Compare LNIB.
`notebook a computer about the same size as a looseleaf notebook,
`weighing less than 6 pounds (2.7 kg). Notebooks are slightly smaller
`than laptop computers, which can weigh up to 8 pounds (3.6 kg).
`Usage note: The distinction between "laptop" and "notebook" has
`become blurred; all present-day laptop computers are notebooks by the
`standards of a few years ago.
`
`4
`
`

`

`voken
`
`538
`
`conversations through the Internet or through IP networks. Several pro(cid:173)
`tocols are used for this purpose. See INTERNET TELEPHONY; PROTOCOL.
`voken (virtual token) an advertisement that appears over the contents
`of a browser window, but not in a window of its own. Compare POP-UP
`AD.
`The voken can move around the screen, rotate, and blink to attract
`attention. A moving voken can trick you into clicking on it -
`thus
`going to the advertiser's site - when you meant to click on something
`else, but it got in the way.
`volatile not permanent; erased when turned off. The memory (RAM) of a
`computer is volatile; that is, it goes blank when power is removed. Flash
`memory and disks are non-volatile. In some programming languages,
`a variable is declared volatile if it can be changed by something
`outside the program.
`volt the unit of measure of electric potential. If a potential of 1 volt is
`applied to a resistance of 1 ohm, then a current of 1 ampere will flow
`through the resistance. (See OHM'S LAW.)
`volume
`1. an individual diskette, disk, or tape.
`2.
`the perceived loudness of a sound. The volume control on a sound
`card may be a knob on the card itself, a setting made in software, or
`both.
`volume serial number an identifying number assigned to a diskette,
`disk, or tape by OS/2, Windows 95 and later, or other operating systems.
`Volume serial numbers ensure that the computer will know when the
`disk or tape in a drive is changed.
`Von Neumann architecture a type of computer design in which
`programs and data are stored in a single kind of memory. Contrast
`HARVARD ARCHITECTURE. See COMPUTER ARCHITECTURE.
`Von Neumann, John (1903-1957) mathematician who worked on
`one of the earliest computers and developed the concept of storing
`programs in memory.
`VPN (virtual private network) a network where data is transferred over
`the Internet using security features preventing unauthorized access.
`VRAM (video random access memory) RAM that is specially designed
`for use in video cards. Commonly, it can be read and written simulta(cid:173)
`neously so that the generation of the display is not interrupted when
`the CPU needs to place data in it.
`VRML (Virtual Reality Markup Language or Virtual Reality Model(cid:173)
`ing Language) a programming language developed by Mark Pesce and
`Tony Parisi to describe three-dimensional objects for graphical display.
`A VRML program describes a "world" of virtual objects that a person
`
`539
`#VRML V1.0 ascii
`
`Separator {
`Separator {
`# Black
`Transfm
`Materiaj
`Cube { '
`}
`Separator {
`#Ball
`Transfo1
`MateriaJ
`
`Sphere i
`}
`Separator {
`# Middle
`MateriaJ
`Cube { i.
`}
`Separator {
`# Block
`Transfor
`Cube { v;
`}
`Separator {
`# Block
`Transfor
`Cube { v;
`}
`
`}
`
`FIGUF
`
`can walkorfty thro1
`from a specified pc
`can respond to m01
`Figure 302 sho'
`It depicts a sphere a
`language, a "separa
`shapes. Figure 303:
`with a VRML BRO"'
`programs can provi
`VSN see VOLUME SE!
`VT-100 a computer
`that had a major im
`provided convenier
`the screen, and sel
`SCREEN CONTROL).
`personal-computer(cid:173)
`implementati ons oi
`
`5
`
`