Access number

Telephone number dialed to access an online service or Internet provider.

Acronym

A word formed from the initial letters of each of the successive parts or major parts of a compound term. Examples: BTW (by the way), FYI (for your information), IMHO (in my humble opinion).
Acronym Finder is a searchable database containing common acronyms and abbreviations about all subjects, with a focus on computers, technology, telecommunications, and the military.

Address

The string of characters that you must give an electronic mail program to direct a message to a particular person. The term "Internet address" often refers to an assigned number, which identifies a host on this network.

ANSI

(1) ANSI is an organization that sets standards.

(2) 'ANSI graphics' (ref. the term ANSI-BBS) is a set of cursor control codes that originated on the VT100 terminal. Many online services use them to enhance their transmission of characters to communication programs. The escape character, followed by other characters, are used to move the cursor on the screen, change color, and more.

ASCII

The American Standard Code for Information Interchange. A standard seven- bit code created to achieve compatibility between various types of data processing equipment. ASCII, pronounced "ask-key," is the common code for microcomputer equipment.
The Standard ASCII Character Set consists of 128 decimal numbers ranging from zero through 127 assigned to letters, numbers, punctuation marks, and the most common special characters. Each code can be represented by a 7 digit binary number: 0000000 through 1111111.
The Extended ASCII Character Set also consists of 128 decimal numbers and ranges from 128 through 255 representing additional special, mathematical, graphic, and foreign characters.

ASCII download

Retrieval of plain ASCII text (without special codes). Normally, it takes place without automatic error correction, but it is typically managed by XON/XOFF flow control.

Asynchronous transfer

Serial communication between two computers. When signals are sent to a computer at irregular intervals, they are described as asynchronous. Data is sent at irregular intervals by preceding each character with a start bit and following it with a stop bit.
Asynchronous transmission allows a character to be sent at random after the preceding character has been sent, without regard to any timing device. So, in case of line noise, the modem can find out right away where the next byte should start.

Autodial

When a modem dials a telephone number automatically. Autodial may be started by the user entering the number manually, or the number may be sent automatically by the communications program (for example after having been selected from a phone register).

Bandwidth

How much you can send through a connection. Usually measured in bits-per- second.

Baud

A unit of measurement that shows the number of discrete signal elements, such as bits that can be sent per second.
Bits per second (bps) is the number of binary digits sent in one second. There is a difference between bps and baud rate, and the two are often confused. For example, a device such as a modem said to send at 2400 baud is not correct. It actually sends 2400 bits per second.
Both baud rate and bps refer to the rate at which the bits within a single frame are sent. The gaps between the frames can be of variable length. Accordingly, neither baud rate nor bps refer accurately to the rate at which information is actually being transferred.

BBS

Bulletin Board or Bulletin Board System. See Bulletin Board.

Big5

Coding scheme developed in Taiwan for using Chinese on computers. There are varieties of Big5 codes, the most common being ET Big5 (the code used by the Taiwanese program ETen, pronounced Yi3tian1) and HKU Big5 (the code used for programs developed at Hong Kong University).
ET Big5 files must be read with the ETen operating system. Check out the Archie server at telnet://archie.TWNIC.NET (login: archie) to locate software and get more information. Also, check Mojikyo.

Binary

The base 2 number system in which only the digits 1 and 0 are used is called the binary system. The binary system lets us express any number, if we have enough bits, as a combination of 1's and 0's. Also used to express conditions like on/off, true/false, yes/no.

Binhex

Macintosh software and documents (other than text files) are often "encoded" into text files for transmission over the network. A common standard for such encoding is referred to as BinHex. You can usually tell that a file contains a BinHex encoded Mac file as the file name ends in ".hqx".
BinHex5.0 format is a MacBinary format, while BinHex 4.0 files are Macintosh ASCII format.
To keep transmission times short, the BinHexed files are often "compressed" using a utility like StuffIt. To reconstitute the Mac application or document you may need to "un-StuffIt." The freeware program, StuffIt Expander, will BinHex and unstuff most Mac files. Uncompression programs are available from archives on the Internet. Examples: xbin23.zip (DOS), mcvert (Unix), and binhex (VM/CMS).

Bits

Bit is an abbreviation for Binary digIT. Computer words and data are made- up of bits, the smallest unit of information.
A bit can be either zero or one, represented in a circuit by an off or on state, respectively. The bits are set on or off to store data, or to form a code that in turn sends instructions to the computer's central processing unit.

Bits per second (bps)

Bits per second (bps) is the number of binary digits sent in one second. It refers to the rate at which the bits within a single frame are sent ('frame' is another term for 'packet'). The gaps between frames can be of variable length. Accordingly, bps does not refer to the rate at which information is actually being transferred.
We usually estimate the number of characters transferred per second (cps) by dividing the number of bps by 10. Example: 2400 bps transfers around 240 characters per second.

Boolean

A Boolean search is a search that allows logical relations between parts. This means that you power your request with the ability to find all relevant documents that fulfill one condition AND (OR) another one. Other common operators include NOT and NEAR. The search algorithm is built on the algebraic theories of the English mathematician George Booles.

Bounce

The return of a piece of mail because of an error in its delivery.

Bps

Abbreviation for bits per second. See above.

Browse

To view and possibly edit a file of data on screen similar to handling text in a word processing document.

BTW

(By The Way) -- A shorthand appended to a comment written in an online forum.

Bulletin board

A computer, often a microcomputer, set up to receive calls and work as an online service. The BBSes let users communicate with each other through message bases, and exchange files. They may also offer other services (like news, database searches, and online shopping).

Carrier

Carrier is the tone modems send over a phone line before any data is sent on it. This tone has a fixed frequency and a fixed amplitude. It is then changed to show data.

Character

Here used about a letter, a number or another typographical symbol or code. For a list of special, email and .html characters, see 123Promote.

CCITT

The Consultative Committee for International Telephony and Telegraphy. Was an international consultative committee, organized by the United Nations. Now replaced by ITU-TSS. See ITU (below).

COM port

A COM port (or communication port) is a communications channel or pathway over which data is transferred between remote computing devices.
MS-DOS computers may have as many as four COM ports, COM1, COM2, COM3, and COM4. These are serial ports most often used with a modem to set up a communications channel over telephone lines. They can also be used to send data to a serial printer, or to connect a serial mouse.

Compress

(1) To compact data to save space.

(2) Common compression function on the Internet. Depending on the distribution of data in a file, compression may reduce its size by 25% to 70%.
COMPRESS files are often, but not always, noted with the file extension .Z. Data archive and compression processes can be combined to form files like filename.tar.z (see TAR below).
If you download a file with a file type showing that it is compressed, you will need a program to expand it before you can use it. Search the net for files starting with 'comp' (as in COMP430D.EXE) to find programs that can expand .Z-files.

Conference

Also called mailing list, web board, SIG (Special Interest Group), Forum, RoundTable, Echo. A conference is an area on a bulletin board or online service set up as a mini board. Most conferences have separate message bases and often also file libraries and bulletins. Conferences are focused on topics, like politics, games, multimedia and product support.

Connect time

A term used for the hours, minutes, and seconds that a user is connected to an online service. On several commercial services, users have to pay for connect time.

cps

Characters per second. See Bits per second.

Cryptography

Coding for privacy.

Cyrillic

There are several different coding systems for Cyrillic characters (Russian). Most important are the KOI-8 Unix standard, and CP-1225, primarily used for Microsoft Windows.
Cyrillic fonts and keyboard maps are available from several sources. See http://www.free.net/Docs/cyrillic/notes.en.html for information.

Data

Information of any kind, including binary, decimal or hexadecimal numbers, integer numbers, text strings, etc.

Database

A database is a highly structured file (or set of files) that tries to provide all the information assigned to a particular subject and to allow programs to access only items they need.
Online services offer databases that users can search to find full-text or bibliographic references to desired topics.

DCE/DTE

Data Communications Equipment/Data Terminal Equipment. Equipment connected to an RS232 connector must be either a DCE (like a modem or a printer) or a DTE (computer or terminal). The term defines the types of equipment that will "talk" and "listen."

Decompression

Files available from online archives are often compressed to save space, and reduce retrieval time. A FAQ about how to decompress 'anything' is regularly posted to the comp.compression newsgroup.

Default

When a value, parameter, attribute, or option is assigned by a communications program, modem, or online system unless something else is specified, it is called the default.
For example, communication programs often have prespecified values for baud rate, bit size and parity that are used unless alternative values are given. These prespecified values are called the defaults.
Some services give users a choice between two or more options. If a selection is not made by the user, then a selection is automatically assigned, by default.

Dial-up access

An indirect connection to the Internet or an online service through a modem or a digital phone network adapter.

Downloading

The transfer of data from an online service and "down" to your computers' disk.

DTR

Data Terminal Ready is a circuit which, when ON, tells the modem that your computer is ready to communicate. Most modems are unable to tell your computer that a connection has been set up with a remote computer before this circuit has been switched off. If your computer turns this signal OFF, while it is in a dialog with a remote computer, the modem will normally disconnect.

Duplex

Describes how you see text entered by the keyboard. When the setting is HALF DUPLEX, all characters entered on your computer for transfer to an online service (or your modem) will be displayed. In addition, you will normally receive an echo from the online service (or modem). The result will often 'bbee lliikkee tthhiiss'.
When using the setting FULL DUPLEX, typed characters will not be shown. What you see, are characters echoed back to you from the online service and/or your modem.

ECHO

(1) When data is being sent, the receiving device often resends the information back so the sending device can be sure it was received correctly.

(2) Term used on FidoNet for this network's system of exchanging conferences (parallel conferencing).

Email

Abbreviation for Electronic Mail.

Ethernet

A very common method of networking computers in a LAN (Local Area Network).

File Name Extensions

Consult the Whatis.com list of file name extensions or suffixes that indicate the format or usage of a file. There's also a brief description of that format.

File server

A file server is a device "serving" files to everyone on a network. It allows everyone on the network to get files in a single place, on one computer. Typically, it is a combination computer, data management software, and large capacity hard disk drive.

File transfer

The copying of a file from one computer to another over a computer network.

Flame

A "flame" is a conference message sent by someone who disagrees so violently that they are willing to sink to personal attacks. Flames can be extremely annoying, and can get the writer banished from several conference networks.

Freeware

A program, text, or file in which the author still holds the copyright but allows the item to be used and distributed free of charge.

Full duplex

The term full-duplex means the transmission of data in two directions simultaneously as from a terminal to a computer or from the computer to the terminal. Full-duplex is simultaneous two-way communication.

Full-text database

A database containing the full text of an article, a chapter in a book, or a book. The contents are not limited to abstracted information (indexes, bibliographic information).

Gateway

In this book, the term gateway is used about an interconnection between two (or more) online services, set up to let a user of one service use the other service's offerings through the first service's user interface.
The term also has other meanings:
A gateway provides an interconnection between two networks with different communications protocols. Gateways operate at the 4th through 7th layer of the OSI model. For example, a PAD (a packet assembler/disassembler) is a device used to interface non-X.25 devices to an X.25 network. The PAD serves as a gateway. Protocol converters are gateways between networks.
The gateway, provided by an adapter card in a workstation, enables the network to perform as if it were a mainframe terminal connected directly to the mainframe.

GuoBiao

Coding scheme for using Chinese on computers developed in mainland China.

Half duplex

The term half-duplex means the transmission of data in either direction but only one direction at a time.

Ham

Amateur radio.

Handle

An alias used on a bulletin board or online service instead of your real name. Often used in chats.

Header

(1) In an email message, the part that precedes the body of a message and contains, among other things, the message originator, date and time.

(2) On a packet switched network, the portion of a package, preceding the actual data, containing source and destination addresses, and error checking and other fields.

Host

A term for host computer, remote computer or online service. Here, we use it about a timesharing computer, a BBS system, or a central computer that controls a network and delivers online services.

Intranet

An internal (corporate) network using Internet technology. Usually it involves the use of the TCP/IP protocols.
Pointers for more information:

http://www.intrack.com/intranet/
http://www.innergy.com/ix/index.html

ISDN

A technology being offered by many telephone carriers. ISDN combines voice and digital network services in a single medium, making it possible to offer customers digital data services as well as voice connections through a single "wire." The standards that define ISDN are specified by ITU-TSS. Connection speed is typically up to 128 Kbps. For more information, visit http://www.itu.int/home/Search/, and enter "isdn" as a search term.

ISO

The International Organization for Standardization. A voluntary, nontreaty organization responsible for creating international standards in many areas, including computers and communications. Its members are the national standards organizations of the 89 member countries, including ANSI for the U.S. ISO is coordinator of the main Internet networking standards that are in use today.

ITU

The International Telecommunication Union, a United Nations treaty organization based in Geneva, Switzerland. Membership includes Telephone, governmental Post, and Telegraph Authorities, scientific and trade associations, and private companies.
ITU consists of three "sectors:" the Radiocommunication Sector, the Telecommunication Standardization Sector (TSS), and the Development Sector.
ITU-TSS sets international communications recommendations. These are often adopted as standards. It also develops interface, modem, and data network recommendations.
A wide range of ITU documents is available from their server.
ITU-TSS is the Standards Sector of ITU .

JIS

A Japanese industry standard code for presenting the Japanese character set Kanji on computers. JIS defines special ranges of user-defined characters. Only the most popular ones are included. The newer Shift JIS standard sets aside certain character codes to signal the start of a two-character sequence. Together, these define a single Kanji metacharacter.
There are many oddities to be found in handling Kanji over the network. Sending JIS-encoded messages through the Internet is done using a 7-bit code, called "OLD JIS" (standardized on JUNET). Unfortunately, it incorporates the ESC character, which some systems will filter out. This problem can be overcome by using UUENCODing.
Kidlink operates two Japanese language mailing lists: KIDLEADER-JAPANESE (for teachers and coordinators), and KIDCAFE-JAPANESE (for children only). See their "How to send and receive Kanji text" help file.
See http://www.sla.purdue.edu/academic/fll/JapanProj/Je-mail/ for more about sending and receiving electronic mail in Japanese.

JPEG (JPG)

Standardized compression method for full-color and gray-scale images that often reduces the size of bitmapped images by a factor of 10 or more with little or no discernible image degradation. Designed to handle "real-world" scenes, for example scanned photographs. Cartoons, line drawings, and other non-realistic images are not JPEG's strong suit. On that sort of material you may get poor image quality and/or little compression.

KB

Kilobyte. A unit of data storage size that represents 1024 characters of information.

Kbits

1,000 bits.

LAN

Local Area Network. A data network intended to serve an area of only a few square kilometers or less.

LDAP

The Lightweight Directory Access Protocol. Email address directory. See the LDAP home page . The LDAP protocol is described in RFC-1777, and is an open standard for directory services on the Internet.

Leased-line

Refers to a phone line that is rented for exclusive 24-hour, 7-days-a-week use from your location to another location.

Library

is used on online services about a collection of related databases (that you may search in) or files (that may be retrieved).

Login

Noun: The account name used to gain access to a computer system. Not a secret (contrast with Password).

Verb: The act of entering into a computer system, for example, "Login to the WELL and then go to the GBN conference."

Lurking

No active participation by a subscriber to a mailing list, a conference, or Usenet newsgroup. A person who is lurking is just listening to the discussion.

Mail Gateway

A machine that connects to two or more electronic mail systems (including dissimilar mail systems) and transfers messages among them.

Mail server

A software program that distributes files or information in response to requests sent by email.

Megabit (Mb)

2^2 bits of information. Usually used to express a data transfer rate, as in, 1 megabit/second (= 1Mbps).

MHS

(1) Message handling Service. Electronic mail software from Action Technologies licensed by Novell for its Netware operating systems. Provides message routing and store and forward capabilities. MHS has gateways into PROFS, and X.400 message systems. It also has a directory naming service and binary attachments.

(2) Message Handling System. The standard defined by ITU-TSS as X.400 and by ISO as Message-Oriented Text Interchange Standard (MOTIS). MHS is the X.400 family of services and protocols that provides the functions for global email transfer among local mail systems.

MIDI

Musical Instrument Digital Interface. A specification that standardizes the interface between computers and digital devices that simulate musical instruments. Rather than transmit bulky digitized sound samples, a computer generates music on a MIDI synthesizer by sending commands just a few bytes in length characterizing the pitch and duration of sounds (and the instruments that produce them). Each channel of a MIDI synthesizer corresponds to a different instrument, or "voice," and you can program several channels simultaneously to produce symphonic sound.

Modem

An acronym for MOdulator-DEModulator. It is a device that converts digital data from a computer or terminal into analog data that can be sent over telephone lines. On the receiving end, it converts the analog data back to digital data.
Most modern modems can handle the dialing and answering of a telephone call and generate the speed of the data transmission, measured in bits per second, or baud rates. The telephone industry sometimes refers to a modem as a dataset.

Moderator

A person, or a small group of people, who manage moderated mailing lists and newsgroups. Moderators are responsible for deciding which email submissions are passed on to list.

Mojikyo

The Mojikyo font set (aka Konjaku Mojikyo, the 'Mirror of characters of old and new days'), is a new approach to handling Chinese characters on personal computers. It uses TrueType fonts for Japanese, Chinese, Vietnamese, Korean, 'Oracle Bone' (kookotsu-bun) and Siddham characters.

MPEG

Motion Picture Experts Group. A multimedia video playback standard that allows digital video to be compressed using a combination of JPEG image compression and differencing (encoding a video sequence by recording differences between frames rather than entire images of each frame).
There are two MPEG standards: MPEG-1, which supports a playback quality roughly equal to that of a VCR, and MPEG-2, which supports high-quality digital video.
MP3 stands MPEG-1 layer 3, a method of storing high quality music files on a disk in such a way that the file size is relatively small. More at http://www.mp3.com/dummies.html.

MUD

Multiple User Dimension, Multiple User Dungeon, or Multiple User Dialogue. A computer program which users can log into and explore. Each user takes control of a computerized persona/avatar/incarnation/character. You can walk around, chat with other characters, explore dangerous monster-infested areas, solve puzzles, and even create your very own rooms, descriptions and items.
For information, retrieve the various MUD FAQs from these directories

http://www.faqs.org/faqs/games/mud-faq/
http://tecfa.unige.ch/pub/documentation/MUD/

No>m

The No>m Standard Code for Information Interchange (NSCII) is a 16-bit character encoding standard used in Vietnam. No>m has been the writing system, based on ideographic (Chinese) characters, in use since the tenth century for the spoken Vietnamese language.

NAPLPS

North American Presentation-Level Protocol Syntax. A text and graphics data transmission format for sending large amounts of information between computers.

Netiquette

A pun on "etiquette" referring to proper behavior on a network.

Network

A data communications system that interconnects computer systems at various sites.

Nodes

Devices on a network that demand or supply services or where transmission paths are connected. Node is often used instead of workstation.

NUA

Network User Address. The network address in a packet data network. The electronic number that is sent to the network to connect to an online service. Also, called X.121 address.

NUI

Network User Identification. The user name/password that you use to get access to (and use) a commercial packet switched network.

Offline

has the opposite meaning of "Online" (see below). It signifies that your computer is not in direct communication with a remote online service.

Offline Reader

A computer program making the handling of mail and files from online services easier (and cheaper). Some also provides automatic mail and file transfers.

Online

Being connected via modem or a digital phone adapter to a computer service.

OSI

Open System Interconnection. A set of protocols designed to be an international standard method for connecting unlike computers and networks. A FAQ, Introductory information about OSI, is posted each month to the comp.protocols.iso, comp.answers, and news.answers newsgroups.

Packet

(1) A group of bits sent by a modem that make up a byte of information.

(2) A group of bytes sent by a file transfer protocol.

Packet data networks

Also called Packet Switching Networks (PDN). Value added networks offering long distance computer communications. They let users access a remote computer, by dialing a local node, or access point.
The packet data networks use high speed digital links, which can be land lines or satellite communications, to send data from one computer to another using packets of data. They use synchronous communications, usually with the X.25 protocol. The routes are continually optimized, and successive packets of the same message need not necessarily follow the same path.

Packet radio

is a method of communications by radio in which digital information prepared on a computer is converted to short, swift audio bursts ("packets") by a "terminal node controller" or "packet controller," and sent through a radio to another location where a similar station delivers it error-free to the receiving computer. It can send text as well as binary files.

Packet switching

Sending data in packets through a network to some remote location. The data to be sent is subdivided into individual packets of data, each having a unique identification and carrying its destination address. This allows each packet to go by a different route. The packet ID lets the data be reassembled in proper sequence.

Password

A code used to gain access to a locked system. Good passwords contain letters and non-letters and are not simple combinations such as "virtue7". A good password might be: Ho/t$1-6.

PDF

A method for displaying information on computers made by Adobe Acrobat. PlanetPDF is a useful resource for everything PDF. Resources include news, tools and plugins, articles and papers, information for developers, tips, and a forum.

Petabit

A million billion bits.

Port

Three meanings. First, a place where information goes into or out of a computer, or both. For example, the "serial port" on a person computer is where a modem may be connected. (See COM Port above.)
On the Internet, "port" often refers to a number that is part of a URL, appearing after a colon (:) right after the domain name. Every service on an Internet server "listens" on a particular port number on that server. Most services have standard port numbers. For example, Web servers normally listen on port 80. Services can also listen on non-standard ports, in which case the port number must be specified in a URL when accessing the server, so you might see a URL of the form:

gopher://peg.cwis.uci.edu:7000/

This shows a gopher server running on a non-standard port (the standard gopher port is 70).
Finally, "port" also refers to translating a piece of software to bring it from one type of computer system to another, for example to translate a Windows program to make it run on a Macintosh.

Prompt

Several times during interactive dialogs with online services, the flow of data stops while the host computer waits for commands from the user. At this point, the service often presents the user with a reminder, a cue, a prompt. These are some typical prompts:

    ? 
    ! 
    WHAT NOW? 
    (Read) next letter - 
    ulrik 1> 
    System News - 5000> 
    Enter #, <H>elp, or <CR> to continue? 
    Action ==> (Inbox) 
    Command: 
    Enter command or <RETURN> 
    -->

Protocol

A formal description of message formats and the rules two computers must follow to exchange messages. Protocols can describe low-level details of machine-to-machine interface (for example, the order in which bits and bytes are sent across the wire), or high-level exchanges between allocation programs (for example, the way in which two programs transfer a file across the Internet).

PTT

Postal Telegraph and Telephone. A telephone service provider, often a monopoly, in a particular country.

Public domain

Free from copyrights or patents, these programs, texts or files may be used by the public without any payments to the creators.

Qalam

is an Arabic-Latin-Arabic transliteration system between Arabic script languages and the Latin script embodied in the ASCII character set. The Qalam system is designed to transliterate Arabic script languages for computer mediated communication by individuals literate in those languages.

QWK

Qwikmail. A n offline message file format for bulletin boards offering mail through a QMail Door. The .QWK door and file format has been used to develop entire BBS networks (example: ILINK.)
There are QWK-format mail readers for Apple, Amiga, Atari, C64/C128, CoCo/OS9, CP/M, Macintosh, MS-DOS, OS/2, Unix, Windows and Windows NT.

Real-time

Having the appearance of immediate action. For example, typing messages that appear on another's monitor almost instantly.

Router

A special-purpose computer (or software package) that handles the connection between two or more networks. Routers spend all their time looking at the destination addresses of the packets passing through them, and deciding which route to send them on.

Routing

The process of delivering a message across a network or networks via the most proper path. While simple in principle, routing is a specialized, complex science, influenced by a plethora of factors. The more networks are interconnected, the more esoteric routing is set to become.

Script files

A set of commands that enable a communications program to execute a given set of tasks automatically (macro commands).

Search engines

A search engine looks up the word(s) you input in an index to Web documents. Indexes vary in size. None will be completely comprehensive and up-to-date though most are updated regularly and some are huge. Some also cover Usenet news archives, and there are others for gopher servers.

Server

A computer or a software package that provides a specific kind of service to client software running on other computers. The term can refer to a particular piece of software, such as a WWW server, or to the machine on which the software is running. (Example: mail server is down today, that's why email isn't getting out.")
A single server machine could have several different server software packages running on it, thus providing many different servers to clients on the network.

Shareware

Copyrighted programs, texts, or other types of application files sold on a try-before-you-buy basis. If you continue using the item past a certain evaluation period, you must pay the author a given "registration fee." Also often referred to as "user-supported."

Snail mail

A pejorative term referring to the national postal service in different countries.

Spam (or Spamming)

An inappropriate attempt to use a mailing list, a conference, or another networked communications facility as if it was a broadcast medium by sending the same message to many people who didn't ask for it.

String search

A method for searching a database. Works like the search function in a common word processor program.
On online services, your commands will often search the full document (including the title, subtitles, keywords, and the full text). Sometimes, string searches just return a line or a few lines around the hit. In other cases, they return the full screen or the full document.

Sysop

Common name used on bulletin boards for System Operator. This is the person in charge of maintenance and helping users.

System

Generic name for a computer with connected equipment or for an online service or bulletin board.

T1

Leased lines come in different grades of which T-1 and T-3 are examples. A T-1 link provides a communications link at up to 2.048 megabits per second.

T3

A term for a digital carrier facility used to send a DS-3 formatted digital signal at 44.746 megabits per second.

TAR

.TAR or .tar is a file name extension used by a Unix utility for archiving files, often used with "compress." The resulting files can contain both files and directories, and may include the subdirectory structure needed to restore the files. The way in which a "tarred" file is "untarred" depends on the operating system you are using. Utilities to extract on DOS machines may be retrieved from many sources around the net.

Terminal emulator

A program that allows a computer to emulate a terminal. The workstation appears as a given type of terminal to the remote host.

Unicode

A 16 bit standard system for encoding characters of all the world's languages. The first 128 codes of Unicode are the same as in ASCII. The system uses two bytes for each character rather than one, and can handle 65,536 character combinations rather than ASCII's just 256.
Unicode can house the alphabets of most of the world's languages, including a complete complement of Chinese, Korean and Japanese specific characters. ISO defines a four-byte character set for world alphabets, but uses Unicode as a subset.

Unix

An operating system that supports multi-user and multitasking operations.

Uploading

The act of transferring data from your computer's disk (up) to an online service and storage there.

Virus

A computer virus is a small computer program created by a computer-literate vandal with the purpose of destroying data or even applications programs in other people's computers.

VRML

The Virtual Reality Markup Language aims at extending the World Wide Web into the domain of three-dimensional graphics. VRML "worlds" can depict realistic or otherworldly places, which can contain objects that link to other documents or VRML worlds on the Web. For information, see The Virtual Reality Entertainment Resource Guide.

X.25

A ITU-TSS standard communications protocol used internationally in packet data networks. It provides error-checked communication between packet data networks and their users or other networks.
Rather than sending a stream of bits like a modem, an X.25 router sends packets of data. There are different packet sizes and types. Each packet contains data to be sent, information about the packet's origin, destination, size, and its place in the order of the packets sent. There are clear packets that perform the equivalent of hanging-up the phone. There are reset, restart, and diagnostic packets. On the receiving end, the packet assembler/ disassembler (PAD) in the router translates the packets back into a readable format.

X.400

The ITU-TSS and ISO standard for electronic mail.

X.500

An ITU-TSS and ISO standard for electronic directory services.

More information

Irving Kind's Glossary of Computer Oriented Abbreviations and Acronyms.