Jargon is de rigueur when it comes to the online arena, and it seems that new acronyms for the Web are coined at breakneck speed with each new technological advance. You know the usual suspects—WWW, email, URL—and are probably familiar with others from error messages on your computer or mentions in tech-related articles, but what does it all mean? This comprehensive glossary breaks down Internet lexicon to the basics and will have you cyber-speaking with the best of them in no time.

ASP — Active Server Pages. A Web page that is created dynamically by the Web server and contains both HTML and scripting code. These pages have a .ASP file name extension.

DHTML — Dynamic Hypertext Markup Language. HTML documents with content that changes each time it is viewed. The three pieces that make up DHTML pages are HTML, JavaScript, and cascading style sheets.

DNS — Domain Name System. A database system that translates alphabetic domain names into the numeric IP addresses that are recognized by the Internet.

DSL — Digital Subscriber Line. This technology enables high-speed transmission of digital data over copper telephone lines. In addition to providing a faster connection, DSL allows you to be online and on the phone at the same time.

FTP — File Transfer Protocol. A protocol used to upload files from a workstation to a server or download files from a server to a workstation. Most FTP servers require the user to log on in order to transfer files. When "ftp" appears in a URL, it means the user is connecting to a file server, not a Web server.

GIF — Graphics Interchange Format. A widely supported file format for putting graphics on the Web. Preferable to JPEG for images with only a few distinct colors, such as line drawings and black-and-white images.

HTML — Hypertext Markup Language. The authoring language or code used to create documents on the Web. HTML defines the layout and architecture of a Web page by using different tags and attributes.

HTTP — Hypertext Transfer Protocol. Written in the early 1990s by the Web's inventor, Tim Berners-Lee, this protocol is used to transfer files from a Web server onto a browser in order to view a Web page online. When "http" appears in a URL, it means the user is connecting to a Web server, not a file server.

IM — Instant Messaging. Generally quicker than email, this service allows you to see whether a chosen person is online and, if they are, to exchange messages. In order for IM to work, both must be using the same instant messaging program.

IP Address — Internet Protocol Address. Every computer that communicates over the Internet is assigned a numeric IP Address that identifies the device and distinguishes it from other computers on the Internet.

ISDN — Integrated Services Digital Network. A suite of standards for digital communication over the public telephone network. ISDN delivers a five-fold speed improvement over modems and provides close-to-perfect transmission reliability.

ISP — Internet Service Provider. A company that provides access to the Internet and email for a monthly fee. Some popular ISPs include AOL, Earthlink, MSN, and AT&T Worldnet.

JPEG — Joint Photographic Experts Group. One of the widely supported file formats for putting graphics on the Web. Preferable to GIF for images with continuous color and grayscale-tone images.

Kbps — Kilobits Per Second. A measure of data transfer speed, usually used to indicate how fast the modem transfers data. The higher the number, the faster you can surf.

MP3 — The file extension for MPEG, audio layer 3 (Moving Picture Experts Group), an MP3 is a compressed audio format that greatly reduces file size without much loss in sound quality.

POP — Point of Presence. A telephone number that gives you dial-up access. ISPs generally provide many POPs so that a user can make a local call to gain Internet access.

POP3 — Post Office Protocol, Version 3. A protocol used to retrieve email from a mail server. Most email applications use POP protocol; the latest version, POP 3, can be used with or without SMTP.

PPP — Point-to-Point Protocol. A protocol for communication between computers using TCP/IP, over standard telephone lines, ISDN, and other high-speed connections. It can be used to connect a computer to the Internet, for services such as the World Wide Web and email.

SMTP — Simple Mail Transfer Protocol. A server-to-server protocol for delivering email. This is the standard protocol used on the Internet; it is also used on other TCP/IP networks.

TCP/IP—Transmission Control Protocol on top of Internet Protocol. These protocols were developed to enable communication between different types of computers and networks. By itself, IP functions like a postal system, allowing you to address an item and drop it in the system. TCP/IP functions like a phone, establishing a connection between two hosts so that they can send messages back and forth.

URL—Uniform Resource Locator (formerly Universal Resource Locator). An Internet address that tells a browser where to find a Web page. For example, the URL for Symantec is: http://www.symantec.com/.

XML—Extensible Markup Language. A programming language that allows Web developers to create customized tags that will organize and deliver Web content more efficiently than HTML.