It all started with the development of "Hypertext" in 1965. Hypertext is text in a document that can be linked to other sections of the same document, or other documents altogether. These links are what the web is built upon. Every link in a web page is an example of hypertext.
In 1989, physics researcher Tim Berners-Lee envisioned a revolutionary information-sharing system for computer networks that he felt might foster communication in the high-energy physics community. Berners-Lee wrote up a proposal, entitled "HyperText and CERN" (CERN is an acronym for the Conseil Europeen pour la Recherche Nucleaire, or the European Nuclear Research Council). Berners-Lee circulated this proposal amongst his peers, generating much excitement.
The proposal contained three provisions:
In March of 1991, Berners-Lee's vision became reality. The information-sharing system, newly rechristened as the "World Wide Web" was made available to the physics community through a CERN computer. Because it "served" up batches of cross reference documents specially formatted for this web like informatin-sharing system, the physicists called this type of machine a "Web server."
In January of 1992, the World Wide Web was made available to the public, and by the end of 1992, there were 50 Web servers in operation worldwide. Most of these machines were housed on university campuses.
Then, in early 1993, a University of Illinois at Urbana-Champaign undergrad named Marc Andreessen developed a new interface to the world wide web that he called the Mosiac Browser. Mosiac allowed graphics to be used online for the first time, letting people actually design webpages instead of the solid text based pages available before.
The New York Times called Mosiac the "killer app of the Internet," and its ease of use fueled some fairly explosive growth. By the end of 1993, the number of Web servers jumped to 623.
In 1994, Andreessen teamed up with Silicon Graphics chair Jim Clark to form Netscape Communications Corporation. Because the University of Illinois owned the rights to Mosiac, Andreessen and Clark immediately began marketing their Netscape Navigator, a commercial version of the Mosiac Browser.
Mosiac was later sold to Spry corporation. Spry was then acquired by CompuServe which was then aquired by Worldcom. Worldcom dumped Mosiac, retained the rest of CompuServe's infrastructure, and sold the CompuServe customer roster to a service provider named America Online.
By the mid-1990s, the web had exploded to such a degree that many households were connected online, and many more businesses saw it as new territory to conquer, led by such upstarts as Amazon and E-Toys. And "old school" technology companies such as Microsoft and IBM started changing their entire business strategies to focus on web based products.
Today, an estimated 230,000 Web servers, each containing hundreds of thousands of documents known as "web pages", are in operation.