Internet Glossary

compiled by Peter Y. Chou

Instructor for “Navigating the Internet”
Foothill College, Los Altos Hills, CA

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access— a means of connecting to or getting on the Internet

Acrobat— a software from Adobe Systems that lets you translate Postscript files into a Portable Document Format so that others may view them online even if they don't have the program from which the files were created.

ActiveX— Microsoft technologies for linking desktop applications to theWorld Wide Web. Using programming tools such as Java, Visual Basic, and C++, developers can create interactive web content. ActiveX technology can allow users to view Word and Excel documents directly in a browser.

address— your computer address, made up of your name, an @ symbol, and the computer's domain name on which the user's account resides (e.g.,

ADSL (Asymmetric Digital Subscriber Line)— Like ISDN, ADSL uses standard phone lines to deliver high-speed data communications. But while ISDN's transmission speed is limited to 64 kbps, ADSL technology can deliver upstream (from the user) speeds of 640 kbps and downstream (to the user) speeds of more than 6 mbps. Even better, ADSL uses the portion of a phone line's bandwidth not utilized by voice, allowing for simultaneous voice and data transmission.

alt— alternative newsgroups on a wide range of topics not belonging to the seven major hierarchies

anonymous ftp— servers that makes files on the Internet available to the user through file transfer protocol (ftp). Many Internet sites let you enter "anonymous" as the login ID to gain access to their files.

ANSI— American National Standard Institute disseminates basic standards like ASCII

AOL (American Online)— one of the most popular online services that's easy to use and family oriented [8619 Westwood Center Dr., Vienna, VA 22182; (800)-827-6364]

AppleLink— Apple Computer's official bulletin board system that is merged into eWorld

Archie— a program developed at McGill University, Canada, to sort quickly millions of public files available by anonymous FTP sites around the world

archive— a place where files are stored

ARP (Address Resolution Protocol)—an Internet protocol that makes it possible for TCP/IP to run over a low-level networking standard as over Ethernet networks

ARPANet— a predecessor of the Internet started by the U.S. Defense Department in 1969 for networking research and to make computer networks secure during a nuclear war.

ASCII— American Standard Code for Information Exchange, a universal computer code for English letters & characters that translates letters to binary numbers which computers use internally (e.g., A = 01000001 in ASCII)

asynchronous— transmission that is not regulated by precise timing on the receiving terminal

ATM (Asynchronous Transfer Mode)— a relatively new communications medium suitable for fiber optics that allows networks to transfer data, video, sound, on a switched (in 53-byte "cells"), as opposed to a point-to-point, basis

authoring tool— software to create online documents such as hypertext or multimedia documents


backbone— the system of high-speed connections routing long-haul data transmissions to slower regional datapaths (like sap flowing from tree trunk to branches to leaves)

bandwidth— the frequency width of a transmission channel measured in Hertz; the size of the data pipeline. Information flows faster at higher bandwidths measured in bits/second

baud— speed at which a modem transfer data, measured in bits per second (e.g., a 28.8K baud modem changes the signal it sends on the phone line 28,800 times per second)

BBS (Bulletin Board System)— an online system that offers e-mail, files, graphics, and programs to download. There are over 10,000 BBS in the U.S. Commercial BBS like AOL and Compuserve offer a gateway to the Internet.

binary file— a file of 1s & 0s representing text, graphics, sound, or video. In ftp transfers, a binary file is specified by "bin" or "image" settings.

BITNet— (Because It's Time Network) an international educational network of mostly academic & research sites

bounce— return of e-mail because of an error in its delivery

bps (bits per second)— speed at which bits are transmitted over a communication medium

bridge— a set of hardware & software that lets two different networks appear seamless as one network to users connecting from outside the system

browser— a program that interprets & displays HTML documents; a software like Mosaic, Netscape Navigator, and Microsoft Internet Explorer that lets you surf the World-Wide Web with mouse-clicks to other sites.

burst— a short spurt of data (packets) sent online


C— the preferred programming language on UNIX, and most often used on the Internet

CARL (Colorado Association of Research Libraries)— offers a table of contents service of popular magazines with summaries of articles, and full articles available by fax on request via e-mail (

CERT (Computer Emergency Response Team)— a federally funded organization acting as a center for computer security information on the Internet

chat— a live online interactive communication where someone on the network reads your message as you're typing it

CIX (Commercial Internet Exchange)— a new organization that allows network providers do accounting for commercial traffic (e-mail address:

ClariNet— the primary online vendor of international news for the Internet community available via Usenet

client— the user of a network service or a computer relying upon another for its some or all of its resources.

CNIDR— Clearinghouse for Networked Information Discovery & Retrieval (Research Triangle Park, North Carolina) whose objective is to support the development of network search tools used to retrieve information off the Internet

com— top-level domain name for commercial services

command line— On Unix systems, this is where you type in your commands or instructions to the computer

communication driver— the software that determines how Microsoft Windows mangages serial communications

communications software— a program that tells a modem how to work

comp— one of the 7 major hierarchies of USENET newsgroups featuring computers, software, & computer science

compression— elimination of redundant information in a file so that the data may be stored in less disk space, as well as to make transfer time faster

CompuServe— an extensive international online service with over 1000 databases [5000 Arlington Center Blvd, Columbus, OH 43220; (800)-848-8199]

CoSN (Consortium for School Networking)— a non-profit organization that wants to get networking resources to students and teachers in K-12 schools

country code— top-level domain name identifying a country (e.g., be: Belgium; fr: France; us: United States)

CSLIP— A form of SLIP that compresses header information to improve performance

CSO (Computing Services Office)— a system to search for students & faculty members at a given school

CSS (Cascading Style Sheets)— using HTML tags in the header like a template, so web developers can define a style for an HTML element and then apply it to numerous web pages. H1 headers and body text could be specified in a particular font, size, and color. CSS is a real time-saver since changes are easy, fast, and global. CSS is supported by Netscape Navigator 4.0 & Microsoft Internet Explorer 4.0.

CWIS— Campus Wide Information Systems provide electronic bulletin boards of events at colleges & universities and supplies campus directories, databases, & library holdings

cyberspace— a word coined by William Gibson in his fantasy novel Neuromancer to describe the universe of networked computers and the society that gathers around them


daemon— [from the mythological meaning, later rationalized as the acronym Disk And Execution MONitor] a harmless Unix program that runs in the background invisible to the user. Unix systems use a daemon named sendmail which is invoked when your e-mail is not delivered to the recipient, and you get back your original message plus a "mailer daemon" message.

datagram— the standard format for a data packet as arranged by IP

DHTML (Dynamic HTML)— combines HTML, cascading style sheets, and scripts to make web pages more interactive. Some advantages of DHTML are incorportating layers and making innovative typography to enhance graphic design on the web.

DIALOG— largest supplier of commercial databases which can be reached on telnet at To log on, you need to set up a Dialog account.

Domain Name System— the system locating the IP addresses corresponding to named computers & domains.

domain— last part of an Internet address (e.g.

domain name— a unique name identifying a web site; a virtual address in cyberspace. You could register a domain name with Network Solutions for $70 (2 years).

down— not operating; when you can't access a public site that's having technical problems, that site is down.

download— transfer files or graphics from a host system to your computer using communication software & a modem

DSL (digital subscriber line )— carry data at high speeds over standard copper telephone wires. With DSL, data can be delivered at a rate of 1.5 mbps (30 x faster than through a 56-kbps modem). Also, DSL users can receive voice and data simultaneously, so small offices can have computers plugged to the Internet without interrupting phone connections.


edu— top-level domain name for educational institutions

EFF (Electric Frontier Foundation)— an organization that lobbies for basic Constitutional rights on the networks; often called "conscience of the Internet"

EIP (Enterprise Information Portal)— also known as enterprise portal, business portal, corporate portal, and intranet portals, EIP offer s a hierarchically organized desktop view that eliminates the need to search through massive amounts of data in disparate repositories. Businesses are realizing the benefits of the one-stop access to information. See article “Business Data Finds a Home on Custom Portals” (Tech Week, 2-22-99)

elm— a full-screen e-mail program on Unix systems

EMACS— [from Editing MACroS] a standard Unix text editor preferred by hackers because it can run intelligent programs called macros with a single command. If you're ever stuck in EMACS, Ctrl-X followed by Ctrl-C to quit.

e-mail (electronic mail)— electronic exchange of messages between individuals from one computer to another

emoticon— another name for smiley [e.g. : - ) for happy]

Ethernet— a 10-million bit-per-second networking scheme developed by Xerox PARC and widely used for LANs because it can network many computers

Eudora— a Macintosh program for e-mail invented by Steve Dorner (University of Illinois) in the 1980s and licensed to Qualcomm Inc. (San Diego). Read article “For Inventor of Eudora, Great Fame, No Fortune” (New York Times, 1-21-97)


FAQ (Frequently Asked Questions)— Lists of questions by beginners of a newsgroup with answers from veterans

FARNET— Federation of Advanced Research Networks, a nonprofit group promoting research & education networking at both K-12 schools and colleges

FDDI (Fiber Distributed Data Interface)— an emerging standard for network technology based on fiber optics established by ANSI. FDDI specifies a 100-million bit-per-second data rate using token-ring technology.

film at 11— [MIT: in parody of TV anchors] announcing ordinary events, with a sarcastic implication that these events are earth-shattering ["Virus spreading like wildfire on the Internet. Film at 11."]

finger— allows you to get information about other users on another system using the form "finger@site", provided they have already created a .plan file

firewall — a system that isolates one's computers from external access, as through the Internet, so its data will not be tampered by unauthorized users

flame— an angry response attacking a posting on Usenet or a mailing list which may break out into a "flame war"

followup— a Usenet posting responding to an earlier message (cf. to a reply which is sent by e-mail and not broadcasted to a wider audience)

foobar— [from WWII acronym FUBAR "fouled up beyond all recognition"] whenever you want to refer to something without a name in Usenet or Unix, you can use "foo" (or less often "foobar"). When you refer to two nameless things, you use "foo" & "bar". In a 1938 cartoon, Daffy Duck holds up a sign that reads, "Silence is Foo" (quite a Zen remark).

freenet— community-based networks that don't charge user's fees for online access to public information

freeware— software that's distributed online free of charge

FSF (Free Software Foundation)— devoted to creating free software replacements for proprietary programs.

FTP (File-Transfer Protocol)— a standard protocol for transferring files over the Internet; also used as a verb "ftp this file from"

F2F— Face to Face. When you finally meet those people you've been talking to & corresponding with in cyberspace.

FYI (For Your Information)— a subseries of RFC documents offering basic nontechnical information


gateway— a system providing a connection between different networks and routes data between them

GB (Gigabyte)— a unit of data storage size of a billion bytes of information

GIF (Graphical Interchange Format)— A computer 24-bitmap graphics format developed by CompuServe, for compressing files for faster transfer over the Internet. It is found on picture files as a file extension (portrait.gif)

Gopher— Internet menu system to help you find information

gov— top-level domain name for Federal government [e.g.,]

GUI (Graphic User Interface)— distinguishes the World Wide Web from other programs on the Internet


hacker— originally referring to a programmer who spends a long time refining a computer program to enhance its performance. Those who break into someone's computer system illegally are called "crackers" and not "hackers".

handshake— to connect two modems in synchronization so data transmission is possible

header— a part of a packet preceding the actual data

hits— matches found in a database search under a specific keyword; also number of visits made to a Web site

home page— the graphical door for a Web site; a screen or window of information in which links are included

host— a computer system connected directly to the Internet which provides services to network users

HTML (HyperText Markup Language)— provides codes used to format hypertext documents on the World-Wide Web

HTTP (Hypertext Transport Protocol)— the method used to make typertext browsing possible on the World-Wide Web

hypermedia— displaying graphics, photos, text, audio & video sources through hyperlinks

hypertext— a way to link and access information of various kinds as a web of nodes in which the user can browse at will. Hypertext provides a single user-interface to many large classes of stored information such as reports, notes, databases, computer documentation and online system help. (Tim Berners-Lee, inventor of World-Wide Web)

HyTelnet— a program used to manage telnet functions and to compile a directory of telnet sites


IMHO— Usenet acronym for "In My Humble Opinion"

internet— a network of different networks that communicate via softwares, gateways, routers, and bridges

Internet— the largest global system for linking smaller computer networks together using the TCP/IP suite of protocols for computer communications. Started by the U.S. government for defense purposes, it is now used by businesses, universities, schools, and individuals.

InterNIC— Internet Network Information Center is a free service that answers questions about the Internet [mail: P.O. Box 85608, San Diego, CA 92186; phone: (619) 455-4600; e-mail:; Gopher:]

interoperability— ability of hardware & software on different computer systems to work together & communicate easily by using common protocols

IP (Internet Protocol)— a packet-switching protocol providing a common layer over dissimilar connectinless networks. IP defines the addressing mechanism used to deliver online data

IP address— a network address represented by a 32-bit numeric string of dotted decimal notation (four sets of numbers separated by periods)

ISDN (Integrated services digital network)— a global telecommunications network that provides end-to-end digital connectivity & combines data, voice, & video services in a single line using CCITT standards. Under ISDN, a phone call can transfer 64 kilobits of digital data per second.

ISO (International Standards Organization)— creates the ISO/OSI protocols, standards for international use


Jargon File— a common heritage of the hacker culture begun by Raphael Finkel at Stanford (1975). A later version was published as The Hacker's Dictionary (edited by Guy Steele, Harper & Row, 1983). A polished version was published as The New Hacker's Dictionary (edited by Eric Raymond, MIT Press, 1991). The 3rd edition of The New Hacker's Dictionary (edited by Eric Raymond, MIT Press) was published in Nov. 1996, and has more than 100 new entries and 200 updated ones, and includes the original essays and cartoons.

Java— a programming language developed by Sun Microsystems for adding animation and other action to Web sites. Java is an obeject-oriented language similar to C++ but simplified to eliminate language features that cause common programming errors. Java applications are called applets and can be played back on any web browser that supports Java.

JavaScript— a scripting language developed by Netscape to enable Web authors to design interactive sites. Javascript can interact with HTML source code so that web developers can jazz up their sites with dynamic content.

JPEG (Joint Photographic Experts Group)— a compressed file of graphic images to save disk space and for faster transfer over the Internet. It is found on picture files as a file extension (portrait.jpg or portrait.jpeg)


killfile— a file that filters Usenet postings by excluding messages on certain topics or from certain people

Knowbot— a network tool letting you search several diverse databases consecutively to locate network data and addresses


latency— the delay that happens when data moves through a series of routers to its destination

listserv— online mailing list providing e-mail on specific topics to its subscribers

log off— to disconnect from a host system or network

log on— to connect with an online service or network

lurk— read messages in a Usenet newsgroup, online forum, or mailing lists without ever participating

Lynx— a text-only browser for navigating the Internet


macro— a series of steps (keystrokes, menu commands, etc) programmed into one key combination that lets you execute an entire series of steps at high speed

mail server— a computer that responds to electronic mail requests for information

mailing list— a group discussion via electronic mail on a specific topic in a newsgroup

MBONE— The Multicast Backbone, a tested for moving audio & video information over the Internet

MIME (Multipurpose Internet Mail Extension)— the system for providing graphics & photos through e-mail

misc— one of the 7 major USENET newsgroup's hierarchies with issues that don't fit readily into any of the other categories

modem— equipment that allows computers to connect by telephone lines or cables to other computers

Mosaic— software that provides a graphics interface to the Internet similar to Macintosh or Window interfaces


nameserver— a computer managing Internet names & numeric addresses, turning a domain name into an IP address

NCSA (National Center for Supercomputing Applications)— managed by the University of Illinois and the home of Mosaic, and lots of giant computers

net— top-level domain name for network access providers

Netcom— a large national Internet service provider, and a giant FTP server

netfind— a network search tool that lets you track down user information

Net.god— One who has been online since the beginning, a keeper of the Net's collective history, who knows all and who has done it all.

netiquette— online etiquette guidelines on the Internet

Net.personality— someone who is an attention-getter on Usenet by posting regularly in many different newsgroups

net.police— derogatory term for those Usenet readers who like to impose their standards on other users of the Net who violate their understanding of netiquette.

Netscape— an enhanced version of Mosaic and one of the best graphical interfaces to the Internet

network— computers connected to communicate

newbie— someone new to the Net

news— one of the 7 major Usenet newsgroup's hierarchies discussing issues relating to Usenet & the Internet

newsgroup— a Usenet discussion about a specific topic; now numbering over 12,000 on the Internet

NIC— Network Information Center. A department that helps users with network problems at corporations and universities. The NIC for the Internet is called InterNIC.

nn— a case-sensitive newreader program in Unix to speed up reading Usenet postings by providing only the subject lines of messages in a newsgroup

node— any computer connected to a network; also called host or site (mythology: cf. to jewel of Indra's net)

NSFNET— National Science Foundation Network, a high-speed backbone network that spans the continental United States


offline— computers not connected to a host system or the Net

online— connected to a telecommunications service or network so you could exchange e-mail & find information

org— top-level domain name for non-profit organizations


packet— a block of information traveling over the Internet, complete with addresses for destination & source

PEM (Privacy Enhanced Mail)— let you encrypt your mail before sending it and let the recipient to decrypt it on receipt

Pine— a popular mailbox & letter-writing system using menus to help you navigate through your e-mail. It has an address book so you can set up a mailing list, and allows you to send the same message to many people at once.

Ping— a program that can trace the route a message takes from your site to another site

.plan file— a file that lists anything you want others on the Unix system or the Net to know about you

point of presence— a local phone number for high-speed access maintained by an Internet service provider

POP (Post Office Protocol)— an e-mail protocol used for downloading mail from a mail server

port— a 2-octet binary number identifying an upper level user of TCP on an Internet host computer; also a socket on the back of the Macintosh computer where cords & cables are plugged in.

portal— an Internet gateway, or starting point for web surfing. Portals evolved out of search engines and directories by adding useful services like horoscopes, sports scores, stock quotes, weather, free email and free customized home page. Portals attract eyeballs to stick to their web site in order to sell a lot of advertising banners.
More definitions on web portals.

post— type or upload a message online for others to read

postmaster— the e-mail contact person at a site connected to the Net to ask for information or complain about a user.

PostScript— a printer description language from Adobe Systems that is the standard format for deskstop publishing

POTS (plain old telephone service)— logging on to the Internet using a regular modem that employs your phone line

PPP (Point-to-Point Protocol)— one of two methods (cf. SLIP) for exchanging data packets with the Internet over the telephone. PPP offers data compression & error correction

PRODIGY Service— a popular online service designed for family use with software & activities for both children and parents [445 Hamilton Ave, White Plains, NY 10601; (800)-776-0845]

Project Gutenberg— This group collects and makes available books and articles that are not copyrighted so they may be distributed free online

prompt— a question from the host system to respond to (e.g. "login:" and "password:" prompts to log on)

Prospero— a protocol for a distributed file system that allows you to refer to remote files as if they were on your local system

protocol— a definition controlling network communication

public domain— work of any kind including computer software that's available to the public without copyright infringement [e.g. NASA space photos]


README file— found on a disk of a new software that describes the product and its updates; also found on ftp sites that explains a ftp directory contents and its use.

rec— one of the 7 major USENET newsgroup's hierarchies featuring hobbies & recreational activities

RFC— Request for Comments. Documents describing various protocol standards adopted by the Internet.

rn— a popular case-sensitive Usenet newsreader program for character-based systems. It checks your ".newsrc" file for newsgroups you want to read and omits showing files already read or those you're not interested in seeing.

router— a computer system that determines which path Internet traffic will take to reach its destination


sci— one of the 7 major USENET newsgroup's hierarchies featuring science in a variety of disciplines

server— a computer distributing information or files automatically in response to specifically worded e-mail requests

shareware— software that's freely distributed online where the author requests some nominal fee if you use it often

shell— a program that provides the interface that users work with on Unix systems

SLIP (Serial Line Internet Protocol)— software that allows computers to connect directly to the Internet via a phone line & modem and to receive an IP address

smileys— also called emoticons, symbols used to describe emotion online (more visible when you look at them sideways)— :-) happy; :-( frowning; :-O shouting

SMTP (Simple Mail Transport Proctocol)— the e-mail protocol standard for the Internet for handling electronic mail messages between computers

soc— one of the 7 major USENET newsgroup's hierarchies featuring discussions on society & culture around the world

socket address— the full address of a communicating TCP/IP entity, made up of a 32-bit network address & a 16-bit port number

spam— to send messages to USENET newsgroups that have no relation to that group's discussion topic

stack— a layered view of network operations where each layer is controlled by a particular protocol

StuffIt— a compression program from Aladdin Systems that also decompresses files

surfing— looking for items of interest on the Internet

sysop— system operator. Usually refers to someone who runs a bulletin board system.

sysadmin— system administrator. Someone with computer programming background who operates a host system


T1— a term coined by AT&T for a system that transfers digital signals at 1.544 megabits per second (as opposed to ISDN's 64 kilobits per second).
T3— transferring data across a digital carrier at three times the capacity of T1. Actually it's almost 30 times the capacity. T3 can handle 44.736 megabits of digital data per second.

talk— one of the 7 major USENET newsgroup's hierarchies featuring discussions on controversial issues and debate

TeachText— a word processing program (36K)

TCP/IP— Transmission Control Protocol/Internet Protocol, the communication system for transferring information over a computer that is at the heart of the Internet

Telnet— allows you to log on to distant computers without long distance charges through the Internet

terminal emulation— the process of communicating with a remote computer as if your computer were actually a terminal connected to that computer

thread— a series of connected messages in a newsgroup

token-ring— a local area network technology based on a ring topology. Stations on the ring pass a special message, called a token, around the ring.

transmission— information transport encoded into signals between two or more points

Trumpet Winsock— a shareware TCP/IP stack for Microsoft Windows

TurboGopher— a Macintosh Gopher program for fast file searching on the Internet; available as freeware from ftp//


UNIX— the operating system used by most service providers on the Internet

upload— copy a file from your computer to a host system (e.g., putting your home page on the World-Wide Web)

URL (Uniform Resource Locator)— a name that identifies the exact location of a document, service, or site on the Net

user group— a local, national, or international organization of people interested in technology

Usenet— Internet newsgroups or bulletin-board areas that focus on specific topics

uucp— Unix to Unix copy, a program that copies files from one Unix system to another when they're connected by modem

uuencode— a program that transforms binary files into ASCII files so that you can send them through e-mail.


VBScript — Visual Basic Scripting is a programming language developed by Microsoft for creating scripts (miniprograms) that can be embedded in HTML web pages for viewing with Internet Explorer. These scripts can make web pages more interactive. VBScript also works with Microsoft ActiveX Controls, allowing Web site developers to create forms, interactive multimedia, games, and other Web-based programs. VBScript is similar in functionality to JavaScript.

Veronica— a program that enables you to search Gopher menus for particular keywords on the Internet

Visual Basic— A graphically oriented programming language from Microsoft that can be used to create everything from simple database applications to commercial software packages.

Vortal (Vertical Industry Portal )— a portal web site that provides information and resources for a particular industry. Vortals are the Internet's way of catering to consumers' focused-environment preferences. Vortals provide news, research data, discussions, newsletters, online tools, and many other services that educate users about a specific industry. See EIP.

VRML (Virtual Reality Markup Language)— allows 3-D environments so that on a wall, for example, there might be two-dimensional Web documents you can click on. [Internet World (4-95):68]

VT100— the most commonly used terminal emulation system (made by Digital Equipment) on the Internet


WAIS (Wide Area Information Service)— network of databases with many search options

WAN (Wide Area Network)— any network whose components are geographically dispersed

web— the network of links where texts are linked together in a way that one can go from one concept to another to find the information one wants. (Tim Berners-Lee)

WebCrawler— a search engine that searches by document & content; managed by Brian Pinkerton at University of Washington, which collects documents from the WWW.

WELL— a popular Bay Area bulletin board with full Internet access

WHOIS— a program that enables you to search a database about people and organizations on the network. Network Solution's Whois Directory gives contact info on domain name owners.

windows— simulating Macintosh-like interface on the DOS system in IBM-compatible computers

workstation— a computer running usually on Unix operating system that is generally more powerful than desktip IBM-compatible or Macintosh computers

worm— a computer program that can clone itself

WWW (World Wide Web)— a client-server system that enables you to find Internet resources easier with its use of graphics & sound and its ability to link to other WWW sites


XML (eXtensible Markup Language)— a new Internet language developed by the W3C. XML is a subset of SGML, designed especially for Web documents. XML is a metalanguage, containing a set of rules for constructing other markup languages. It enables designers to create their own customized tags to provide functionality not available with HTML. For example, XML supports links that point to multiple documents, as opposed to HTML links, which can reference just one destination each. Resources for XML may be found at

Xmodem— a protocol for transferring files during direct dial-up communications. Developed by Ward Christensen in 1977, Xmodem has basic error checking to ensure that information isn't lost or corrupted during transfer; it sends data in 128-byte blocks.


Yanoof list— The Inter-Network Mail Guide by Scott Yanoff (University of Wisconsin) that is frequently posted to newsgroups like and news.answers.

Ymodem— a protocol for transferring files during direct dial-up communications. So named because it builds on the earlier Xmodem protocol, Ymodem sends data in 1,024-byte blocks and is consequently faster than Xmodem.

Y2K— the year 2000 problem is sometimes referred to as the Millennium bug or Y2K problem. Many computer programs represent dates in the form MM-DD-YY, and can handle only 20th-century dates that begin with "19". Hence the date January 1, 2000 will be read as 01-01-00 or January 1, 1900. This problem affects a vast amount of software, especially accounting and database systems. The U.S. Social Security Administration, has estimated that it will need to review about 50 million lines of code to correct this problem in its own system. To learn more about Y2K, read Year 2000 FAQ, and the Federal Government's Y2K Page, listing all the economic sectors affected by the Y2K bug.


.z— a UNIX-system compressed file extension which is expandable with UnStuffIt.

zip— the most common compressed-file format for PCs

Zmodem— a protocol for transferring files during direct dial-up communications that supersede Xmodem and Ymodem. It can resume a file transfer after a break in communications.

ZTerm— a communications software for Mac Users for downloading large files from bulletin boards

Books at on Internet Dictionary & Web Glossary

Online Resources for Definitions on Computer Terminology & Internet Technology:

Eric Raymond's The New Hacker's Dictionary (MIT Press) is available as an online reference—
The Jargon File (Version 2.9.6, Aug. 16, 1991) at
The Jargon File (Version 4.1.4, June 17, 1999) at

Here are other Internet Glossaries & Dictionaries you may find helpful:
Internet Glossary
(600 network terms from CNET from "AA" to "Zmodem" including latest definitions such as DHTML)
Internet Glossary from the BBC Online
(106 Online terms defined from "Academic Usage" to "Y2K" by BBC Education)
Internet Glossary from Solution Islands
(Internet terms defined from "access privilege" to "zip" by Solution Islands, a Bay Area ISP)
Computer Currents High-Tech Dictionary
(6,000 definitions of computer terms from A to YUV)
Computing Dictionary
(11,000 definitions of computer terms edited by Denis Howe, England)
(Online dictionary & search engine for computer & Internet technology)
E-Commerce Webopedia
(Source for up-to-date terms, definitions, & acronyms in electronic commerce)

© Peter Y. Chou, Foothill College, 12345 El Monte Rd., Los Altos Hills, CA 94022
email address: (12-14-95, updated 12-14-99)