A small software application. More commonly known as  the term for Java- and JavaScript-based applications. Applets may display animation, or perform sophisticated database queries, or anything else that a small application does. 

A way to describe network capacity. If you've got a 56K modem, you've got a high-bandwidth connection. If you've got a 9,600 bps modem, you've got a low-bandwidth connection. If you want to use digital video, you need a high bandwidth. 

Chances are good that you're using a browser to look at this document. A browser, in most current usage, is any client software that is used for looking at World Wide Web resources. There are other kinds of browsers, too -- for example, image catalogs on CDs are accessed through image-database browsers. Netscape Navigator, Internet Explorer and Mosaic are browsers. So is Lynx.

CERN 

Centre européen pour la recherche nucléaire (European Center for Nuclear Research). The original home of the World Wide Web, Geneva's CERN developed Web protocols as a means for scientific researchers to exchange documents easily. 

Common Gateway Interface. A means for adding functionality to the World Wide Web through scripting. Among other things, CGI scripts can pull records out of an external database. Whenever you run a search on the Internet, you are likely to be using a CGI script. 

A software application that interacts with a server application. In the case of the World Wide Web, a browser client, like Netscape Navigator, will request a file over the Internet from a server program.  

Client/Server is the organizational model for the newer generation of computing. Instead of a host computer running all applications and feeding information to users via dumb terminals, an application on the user's local machine -- the client -- requests and stores information from, and on, the server, but then does much of the processing locally. 

A means for determining how long an HTML file stays in the client browser window before it is refreshed or replaced. Client pull is used, among other things, for routing users from one page to another. 

The nebulous domain that is inhabited by computers and networks. Originated in William Gibson's novel Neuromancer. 

Domain Name 

The unique name for each Internet site. The "top level" of a domain name is the last part, always two or three letters. In the United States, the top-level domains are .com (for commercial organizations), .org (for non-profit organizations), .net (for network providers), .gov (for the Federal government), and .mil (for the military). In other countries, two-letter ISO-standard codes represent each country, e.g. .fr for France, .de for Germany, .uk for the United Kingdom, .ca for Canada, .jp for Japan, and so forth. There are exceptions: .us is occasionally used, especially by municipal and state governments, and foreign companies are allowed access to the .com and .net top-level domains.  

The hierarchy for domain names is represented from right to left. After the top-level domain name come the various sub-domain names. A domain name generally represents one computer. Users' workstations may have their own domain names, or they may simply be assigned IP addresses.  

"Virtual" domain names also exist. These may be aliases to other machines, or they may simply point to a directory on a large host machine that serves as a mail or Web server. This is often done for small businesses and individuals who want to have a presence on the Internet but who do not want to have to set up a physical site. 

Domain Name Server. A piece of software sitting on a server computer that resolves domain names to actual IP addresses. For example, if you wanted to open an Internet telephone call with Morty Miller, whose workstation domain name was mortym.bigcorp.com, you would enter mortym.bigcorp.com. The DNS would determine that mortym.bigcorp.com actually represented the address 158.204.12.78. The DNS would then transmit that IP address to your computer; and your computer would initiate the telephone call. Nodes communicate with each other using IP addresses rather than domain names, though users may never see the actual IP addresses being used. 

E-mail 

Electronic Mail. Electronic communications, sending text messages. 

FAQ 

Frequently Asked Questions. FAQs are text files, posted to Usenet newsgroups, mailing lists, or World Wide Web pages, that have answers to the most commonly asked questions on a particular subject. Although they are often technical in nature (e.g. QuarkXPress FAQ, Gas Chromatography FAQ, etc.), they may exist on any topic under the sun (Esperanto FAQ, Elvis FAQ). If you ask a question on any given subject, you may be referred to the FAQ first. 

Software developed by individuals or small companies that costs nothing to use. The developer retains the copyright to the product, so freeware is not in the public domain. Many Internet utilities are freeware or shareware. 

File Transfer Protocol. FTP is the most common method for transfering files over the Internet. When you want to upload your new Web pages to your server, for example, you send them using FTP. Some FTP sites -- notably university shareware/freeware archives, and software company archives -- allow you to log on anonymously to retrieve public files. There are numerous FTP clients for each operating system -- some using a graphical interface, others require commands to be typed in. 

Graphics Interchange Format. One of the two major graphics file formats on the Web. . GIF is  limited to 256 colors (8-bit color). GIF files have the extension .gif. See also JPEG. 

A billion bytes. A thousand megabytes. Workstations now often have one- or two-gigabyte hard drives. Some servers have mass storage measured in terabytes. 

Host 

A large computer that is accessed for remote services. Host is a bit of an old-fashioned, mainframe-computer term, and has become something of a synonym for server. Terminals are used for connecting to hosts. 

Hypertext Markup Language. The page-coding language for the World Wide Web. Every page that you see on the Web is represented in HTML, whether it was written by a human or by a computer. HTML is relatively simple: you turn attributes on and off using "tags"; and you create graphics and text hyperlinks to pages or files anywhere else on the Internet. HTML pages are viewed using a World Wide Web client program such as Netscape or Mosaic. HTML files end in the file extension .html or .htm. 

Hypertext Transport Protocol. The protocol for serving files on the World Wide Web, HTTP is what browsers and clients use to send and get files. The string http:// makes up the first part of the URL for all World Wide Web pages. 

Text linked to other text or other documents. Apple Computer was an early pioneer in hypertext, publishing an easy-to-program application called HyperCard. The World Wide Web is based upon hypertext links. Clicking on any underlined text in a Web document will prompt your browser to request another resource: another part of the same document, another document, or another file, such as an image or sound. The ability to link resources in this way is what makes the WWW so easy to navigate.

See ISMAP. 

The "world's biggest network". The worldwide net of networks and subnetworks. 

The name for Microsoft's World Wide Web browser.  

Internet Explorer has been gaining ground on Netscape's Navigator. An increasing number of Web authors are writing their pages so that they work with IE as well as the Netscape Navigator browser. 

A unique number consisting of 4 numbers between 0 and 255 punctuated by dots, e.g. 167.241.33.40 

Every computer running TCP/IP has its own unique IP number. Many computers are also assigned domain names, which are easier to remember. 

Also called "imagemap". An image, displayed in a World-Wide Web browser window, that has certain regions mapped out as links to other Web documents. ISMAP requests are processed by CGI scripts sitting on the remote server. 

Internet Service Provider. A company that allows home and corporate users to connect to the Internet. The connection may be part-time PPP or SLIP (for home users), or it may be a full-time ISDN, T-1, or T-3 connection (for companies and clients running full-time servers). 

Java 

Sun Microsystems' new programming language, based on C++ is used to develop "applets" that load from WWW sites. Identical Java applets can be used on any supported platform -- that is, a Macintosh machine will run the same code as a Unix machine or a Windows NT machine. 

An implementation of the Java programming language that allows non-programmers to build Java-based applications easily. 

Joint Photographic Experts' Group. A standard for photographic image compression. JPEG is a "lossy" compression method, which discards data from an image and interpolates the surrounding area. JPEG is also used for compressing frames of the QuickTime movie format, although it is gradually being replaced by MPEG for motion-picture compression. JPEG is capable of storing 24-bit images (millions of colors). JPEG files on the Web have the extension .jpeg or .jpg. See also: GIF 

Kilobyte 

Literally, a thousand bytes, but actually 1,024 bytes. See also: Bit, Megabyte, Gigabyte, Terabyte 

To "log in" is to gain access to a protected computer. As a noun, login is the Unix term for account name. 

An early World Wide Web browser, Lynx is text-only. Though most early World Wide Web pages were easily comprehensible when viewed with text-only browsers, the Web's increasing dependence on graphics makes solutions like Lynx more and more unworkable -- much to the detriment of the visually impaired, who use text-to-speech software to "read" online text. 

An automated e-mail group mailing list. They are often supported by software vendors or user groups to disseminate information on a regular basis. Mailing lists tend to be somewhat more serious than the more anarchical discussion groups on the Usenet. 

A million bits. Transmission speed over local area networks (LANs) is often measured in terms of Megabits per second (Mbps). 

A million bytes. A thousand (1,024, to be exact) kilobytes. Hard-disk space is usually given in megabytes -- but disks are getting bigger, and may be measured in gigabytes or -- on very large server volumes -- terabytes. 

Developed as freeware at NCSA, Mosaic was the first graphical World Wide Web browser. It quickly lost prominence when Mark Andreessen, its principal developer, left NCSA to form Netscape. The source code for Mosaic has been licensed to other software companies; most online services' browsers are based on some Mosaic code. 

Motion Pictures Experts Group. An evolving standard for digital video compression. Often used for creating movie files seen on the World Wide Web. See also JPEG 

"Proper" etiquette on the Internet. 

The colloquial name for the premier World Wide Web browser (which is actually called "Netscape Navigator"), and the name of the company that publishes it.  

Netscape has quickly become the de facto standard-setter for the World Wide Web. Most Web authors write their pages to take advantage of the Netscape Navigator browser; Netscape's server software (Netscape Communications Server and Netscape Commerce Server) are extremely successful commercial server packages; and Netscape Navigator is the first browser to support Sun Microsystems' Java and JavaScript cross-platform development languages.  

Netscape Communications Corporation is the brainchild of Jim Clark, a former Silicon Graphics executive, and Mark Andreessen, the principal developer of Mosaic at NCSA. Netscape now occupies Wall Street legend, because when it was first offered for public sale in August 1995, Netscape stock gained three times its opening value on the first day. 

Network Information Center. An office that assigns domain names on the Internet. Generally, each top-level domain has a NIC. In the United States, the InterNIC assigns all high-level domain names ending with .com, .org, .net, .gov, .mil, and .us. Lower-level domain names are usually assigned by local network administrators. 

Online Service 

A closed, pay-to-use system for e-mail, chat groups, newsgroups, and the like. Online services are much like overgrown BBSs in that one owner controls all the content. Although online services are largely responsible for the initial growth in interest in the Internet, they are beginning to lose customers, who see the Internet as more open, more interesting, and cheaper -- though not always for the faint-of-heart (technically or emotionally). The best-known online services are America Online, CompuServe, and Prodigy. 

Portable Document Format. The file format used by Adobe Acrobat. 

A UNIX-based scripting language that is often used on the World Wide Web. When you submit a complex form from your browser window, for example, the processing of the information may be handled by a Perl script. Perl scripts usually end in the extension .pl. 

Pretty Good Privacy. An open data-encryption standard written by Phil Zimmermann. PGP encrypts documents using the RSA encryption algorithm. PGP is prohibited from export by the US Government. 

A piece of software, often written by a third-party software developer, that loads in conjunction with a host application and extends the functionality of that application. Sometimes called "extension." 

RealAudio 

An Internet-based application, often used as a plug-in to Web browsers, that allows for real-time transmission of audio (e.g., radio broadcasts). 

Robots on the Internet have little to do with the mechanized beasts of science-fiction movies. They automate time-consuming tasks that humans don't like to do, such as gathering database information or checking the validity of hypertext links.  

Search engine 

A special software/hardware implementation that allows users to search the World Wide Web for information based on keywords and other search criteria. The search engine is one of the most useful aspects of the World Wide Web. Some of the major ones are InfoSeek, Alta Vista, Excite, Lycos, Webcrawler, and Yahoo.  

Some search engines find pages through robots that regularly crawl the Web, building databases of information on current pages. Others solely index items that have been submitted manually. Many search engines use both methods. 

Server is a generic term for hardware or software that provides services to clients on a network. A network file server gives users on a network access to shared hard-disk volumes. A World Wide Web server gives Internet users access to documents on that server's volume. A mail server distributes mail to individual users within a local area network.  

Modern computing is increasingly based upon the client/server model. 

Software, usually developed by a small company or an individual, that is distributed via the Internet, online services, and CD-ROMs, and which costs very little (usually $10-$50) to use. Payment of shareware fees is based on the honor system, although an increasing number of shareware programs allow use of the software for a short time, after which the software will fail to function unless the user pays for the software. Many Internet utilities are shareware or freeware. 

A plug-in written by Macromedia that allows interactive multimedia presentations to play in a World Wide Web browser window. 

Secure Hypertext Transmission Protocol. A standard used for transferring secure documents over the World Wide Web. S-HTTP relies upon the RSA encryption algorithm. Presently S-HTTP is used mostly for credit-card purchases over the Web. Pages using this protocol have a URL starting with https:// . 

To spam is to flood Usenet newsgroups or mailing lists with unwanted, unsolicited information. A spam may be advertising material, a get-rich-quick scheme, or a paranoid rant. 

A Silicon Valley hardware and software company, one of the major players in the high-end Unix workstation market. Sun is the developer of Java, the new programming language for the Internet. Sun supports two flavors of Unix: SunOS and Solaris.  

Uniform Resource Locator. The address of any document or other resource on the Internet. URLs always start with a protocol name, like http, ftp, gopher, or telnet, for example, and then usually list the resource's domain name and file path. A typical World Wide Web URL goes like this:  

http://www.bigyellow.com/  

A URL for a particular file on an FTP site would be similar to this:  

ftp://ftp.foodsoft.com/pub/food/fried-eggs-304.sit.hqx  

Some non-standard URLs are used for launching other applications that access information over the Internet. A couple of examples of these are netphone://, for one company's Internet telephony application, and FMP3://, for accessing FileMaker Pro 3 databases. 

VRML 

Virtual Reality Modeling Language. Pronounced -- "vermal."  VRML can be thought of as the HTML of 3-D. Developed partially at Silicon Graphics, the company that brought you the dinosaurs in the movie Jurassic Park. 

The collection of resources across the Internet that is accessed using World Wide Web browsers. It is an effective means for tying together very different types of resources that are scattered across servers all over the world. 

World Wide Web (see). Also, in lowercase, the most common domain-name prefix for World Wide Web servers, e.g. www.netscape.com.