The Technology

How does this exchange of documents work? A quick analogy. An information desk in a museum provides information on request. A visitor walks up to the desk, asks a question, and receives an answer. Until the visitor poses a question, however, the staff have no answer to provide. The relationship between the visitor and the information desk staff is similar to the relationship between a Web server and a Web client.

Servers

Web documents are available from computers running server software. Such computers are referred to as HTTP servers although they might perform other non-Web tasks as well. Servers are connected to the Internet and have documents available to send to other machines upon request. Server software uses a standard transfer protocol called the HyperText Transfer Protocol (HTTP). (Documents, in this context, refers to files that contain text, images, sound, movies or animations, or other file formats.)

Clients

A desktop computer runs client software that asks for information from servers. A client also displays the contents of documents or uses other software to display the contents. (Clients are also called browsers because they make browsing the Web possible.) There are Web clients for many platforms: UNIX, Macintosh, and Microsoft Windows.

The server and the client work together to offer, retrieve, and display the many documents available worldwide.

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