ANSI -- American National Standards Institute -- A private, non-profit organization that facilitates the development of U.S. standards for the information processing industry. ANSI is involved in defining network protocol standards.

application -- Software that performs a specialized, useful function. For example, an electronic mail application such as Eudora, or a Web browser like Netscape.

ARA -- Apple Remote Access -- For Macintosh computers; a software product that allows you to make a network connection over standard phone lines using a modem. An ARA connection is not as fast as a PPP connection, but one advantage to using ARA is that you can access the networked computers and printers from your home. For more information, see the Internet Information Center's Web page on remote network access at yale.

ARPA -- Advanced Research Projects Agency -- The former name of what is now known as DARPA.

ARPAnet -- Advanced Research Projects Agency Network -- An experimental network implemented by the U.S. Defense Department. The first large-scale packet-switched network, ARPAnet was designed to help military researchers develop a communications system that could continue to function despite partial outages (like bomb attacks). It served as the basis for early networking research as well as a central backbone during the development of the Internet.

ASCII -- American Standard Code for Information Interchange -- A document in ASCII code contains primarily textual information and is absent of any special format information, like italics or diacritics. Until recently, much of the information available on the Internet was in the ASCII format in order to facilitate the transfer of data.

baud -- Refers to the speed at which data is transmitted, especially with regard to modems, although "baud" does not correspond exactly with the number of bits that are transmitted per second because it refers to the number of times the medium's "state" changes per second. For example, a 28,800 baud modem changes the signal it sends on the phone line 28,800 times per second. Since each change in state can correspond to several bits of data, the actual bit rate of data transfer may exceed the baud rate. See bits per second.

bit -- binary digit -- The smallest amount of information which may be stored in a computer; the basic unit of measure in a computer.

BITNET -- Because It's Time Network -- An international cooperative network established to promote the non-commercial electronic exchange of information in support of research and education. At one time BITNET was the largest academic network in the world for computer-based communications, but by 1993, the number of academic organizations connected to the Internet outnumbered those participating in BITNET. In 1989 BITNET merged with the Computer + Science Network (CSNET) and adopted the new corporate name, the Corporation for Research and Educational Networking, CREN.

bits per second -- bps -- The speed at which bits are transmitted over a communications medium, such as a phone line.

browser -- A software application that reads hypertext. Applications used to access the World Wide Web (i.e. Netscape and Lynx) are often called Web browsers.

Byte -- B -- One character of information, usually made up of eight bits.

client -- Software that enables you to extract a service from a server on the network. For example, Netscape is a client that allows you to browse the WWW, and Eudora, QuickMail, and Pine are examples of e-mail clients. The relationship between telephones and the telephone company is analogous to the client/server relationship, where the telephone is a client and the telephone company is a server.

CREN -- Corporation for Research and Educational Networking -- An organization established to serve the Internet community with software and services, with a primary focus on "supporting educational outreach, worldwide collaboration, and easy access to information resources throughout the network."

DARPA -- U.S. Department of Defense Advanced Research Projects Agency -- The government agency that funded the ARPAnet and later started the Internet.

DNS -- Domain Name System -- A database system used to translate computer names such as shakespeare.globe.org into numeric Internet addresses like 156.416.16.16.

Ethernet -- A network standard for hardware and data links. Ethernet is the fastest networking technology. See also PPP, ARA, modem.

FAQ -- Either a frequently-asked question, or a list of frequently asked questions (and their answers) usually regarding an Internet site or a newsgroup.

FTP -- File Transfer Protocol -- (a) The Internet standard protocol for transferring files from one computer to another. (b) The act of transferring files from one computer to another using the File Transfer Protocol (FTP).

gateway -- A computer system that allows data transfers between dissimilar, normally incompatible networks.

Gopher -- A menu-based system for exploring Internet resources. Gopher has been largely superseded by the World Wide Web and Web browsers, although much useful information is still available from many Gopher sites. YaleInfo used to be a Gopher site before it migrated to the Web.

header -- The portion of a packet, preceding the actual data, containing source and destination addresses and error-checking fields.

hypertext -- A method of presenting information by using selected words in a text (known as links) to connect to other documents, which may be text, images, software, etc. The World Wide Web is an example of hypertext technology.

HTML -- HyperText Markup Language -- A computer code used to produce hypertext documents which can be read by Web browsers.

HTTP -- HyperText Transport Protocol -- The standard used to transfer World Wide Web data across the Internet.

IP -- Internet Protocol -- A body of rules that forms the foundation for all communications over the Internet.

IP Address -- A unique, specific address assigned to every computer on the Internet.

ISO -- International Organization for Standardization -- An organization that has defined a different set of network protocols, called the ISO/OSI protocols. In theory, the ISO/OSI protocols will eventually replace the Internet protocols.

LISTSERV -- A special messaging program created around a particular theme or topic; numerous LISTSERVs exist, covering various fields and subject areas. Once you've subscribed to a LISTSERV (by sending e-mail to the group's LISTSERV address), messages posted to that list by its members will be sent directly to your e-mail address.

modem -- A piece of equipment that connects a computer to a data transmission line (typically a telephone line).

newsgroup -- A forum which allows users to exchange messages relating to a particular topic or theme. Unlike LISTSERV postings, newsgroup messages are not delivered to a subscriber's e-mail address, but must be retrieved by using a news reader.

nodes -- Specialized devices or computers on a network that communicate with one another either through direct physical links or through intermediate devices such as modems or routers.

packet -- The unit of data sent across a packet-switched network.

packet-switched network -- A network in which data exchanged between nodes are broken into packets that contain origin and destination information, packet length data, the actual data, and a flag that the packet has ended. The Internet is a packet-switched network.

port -- A number that identifies a particular Internet application. When your computer sends a packet to another computer, that packet contains information about what protocol it's using, and what application it's trying to communicate with. The "port number" identifies the application. For example, the Orbis port from the Multi-Protocol Gateway (MPG) is 06520, so if you were to telnet to the MPG without including a port number in the address (umpg.cis.yale.edu), you would get the MPG screen. If, however, you were to attach the appropriate port number to the telnet address (umpg.cis.yale.edu 06520), you would go directly to Orbis, bypassing the MPG screen.

posting -- An individual article sent to a newsgroup or listserv.

PPP -- Point-to-Point Protocol -- A protocol that allows a computer to use the TCP/IP (Internet) protocols with a standard telephone line and a high-speed modem. For more information, see the Internet Information Center's Web page on remote network access at yale.

protocol -- A formal description of the rules two computers must follow to exchange messages or data.

search engine -- A tool which allows keyword searching for relevant sites or information on the Internet.

server -- (a) A computer that controls access to network resources. (b) Software that allows a computer to offer a service to another computer. Other computers contact the server program by means of matching client software.

TCP -- Transmission Control Protocol -- One of the communications protocols on which the Internet is based.

TCP/IP -- Transmission Control Protocol/Internet Protocol -- The two protocols which, together, define the way in which messages (data or commands) are passed among computer networks on the Internet.

Telnet -- a) An application program that allows you to establish a connection with another computer anywhere on the Internet and use the resources available to that computer in a one-to-one connection. For example, you use Telnet to log into the server and read your email. b) The act of using a Telnet program to log in to another computer system.

tn3270 -- a special version of the Telnet program that interacts properly with IBM mainframes.

UNIX -- A computer operating system that supports multi-user and multitasking operations. UNIX was very important in the development of the Internet, although you do not have to use UNIX to use the Internet. The operating system for the Pantheon accounts is UNIX.

URL -- Universal Resource Locator -- Provides a location for data, software, images, etc. URL's are used by Web browsers to locate WWW sites.

WWW -- World Wide Web -- A hypertext-based system for finding and accessing Internet resources.