HTTP = HyperText Transport Protocol.

The standard Internet protocol for the exchange of information on the World Wide Web. Basically, it defines URLs by telling the server what to send to the client. (For example, when you enter a URL in your browser, this actually sends an HTTP command to the Web server directing it to fetch and transmit the requested Web page.)

The client can view Web pages, FTP sites, Gopher sites, Usenet newsgroups, or other areas of the Net. HTTP enables Web authors to code hyperlinks into documents. Once the files are uploaded to the server, those links can be clicked on to initiate a data transfer process. Information is retrieved without any further input from the user (this is known as "transparent access," in which the user doesn't even need to know where the document is coming from or how it was accessed).

HTTP is called a stateless protocol because each command is executed independently, without any knowledge of the commands that came before it. This is the main reason that it is difficult to implement Web sites that react intelligently to user input. This shortcoming of HTTP is being addressed in a number of new technologies, including ActiveX, Java, JavaScript and cookies.