Internet and the World Wide Web

In 1990, Tim Berners-Lee and other scientists at the international organization called CERN (European Center for Nuclear Research) in Geneva, Switzerland, developed a computer protocol called the HyperText Transfer Protocol (HTTP) that became the standard communications language between Internet clients and servers. Exchanges of information on the Internet take place between a server (a computer program that both stores information and transmits it from one computer to another) and a client (also a computer program but one that requests those transmittals of documents from the server). The client is not a person; the person giving instructions to the client is called a user. The first Web server in the United States was the Stanford Linear Accelerator Center (SLAC) in Palo Alto, California. To be able to look at retrieved documents, the user's computer is equipped with browser software. The programmers at CERN also developed a text-based Web browser that was made public in 1992; they also proposed the name World Wide Web for their system.

Documents that comply with the HTTP protocol are called hypertext documents and are written in HyperText Markup Language (HTML) which includes both text and links. Links are formally called hypermedia links or hyperlinks that connect related pieces of information through electronic connections. Through links, users can access arrays of documents identified by these shared links. Documents consisting of text are identified through hypertext; and other kinds of information like photos and other images, sounds, and video are identified as hypermedia. Users find and access hypertext or hypermedia through addresses called Uniform Resource Locators or URLs. URLs often contain the letters "http," "www," and "html" showing that, within the HTTP rules, they want to access the World Wide Web by speaking in HTML.