A Web server is the server software behind the World Wide Web. It listens for requests from a client, such as a browser like Netscape or Microsofts Internet Explorer. When it gets one, it processes that request and returns some data. This data usually takes the form of a formatted page with text and graphics. The browser then renders this data to the best of its ability and presents it to the user. Web servers are in concept very simple programs. They await for requests and fulfill them when received.
Web servers communicate with browsers or other clients using the Hypertext Transfer Protocol (HTTP), which is a simple protocol that standardizes the way requests are sent and processed. This allows a variety of clients to communicate with any vendors server without compatibility problems.
Most of the documents requested are formatted using Hypertext Markup Language (HTML). HTML is a small subset of another markup language called Standard General Markup Language (SGML), which is in wide use by many organizations and the U.S. Government.
