HTTP: The Definitive Guide

Web Clients and Servers

Web content lives onweb servers. Web servers speak the HTTP protocol, so they are often called HTTP servers. These HTTP servers store the Internet’s data and provide the data when it is requested by HTTP clients. The clients send HTTP requests to servers, and servers return the requested data in HTTP responses, as sketched in Figure 1-1. Together, HTTP clients and HTTP servers make up the basic components of the World Wide Web.

Figure 1-1. Web clients and servers

You probably use HTTP clients every day. The most common client is a web browser, such as Microsoft Internet Explorer or Netscape Navigator. Web browsers request HTTP objects from servers and display the objects on your screen.

When you browse to a page, such as “http://www.oreilly.com/index.html,” your browser sends an HTTP request to the server www.oreilly.com (see Figure 1-1). The server tries to find the desired object (in this case, “/index.html”) and, if successful, sends the object to the client in an HTTP response, along with the type of the object, the length of the object, and other information.