IN THIS CHAPTER
The Uniform Resource Locator
Fundamentals of HTTP
Better information through headers
Evolution of the HTTP Protocol
Offer a historical perspective on the main building blocks of the web.
Discuss fundamentals of the scheme for addressing web resources.
Discuss fundamentals of the HTTP protocol.
Set the stage for learning web technologies based on first principles.
For all practical purposes, the web started at CERN back in 1989. That is when Tim Berners-Lee wrote a proposal for a hypertext-based information management system and distributed it among the scientists at CERN. Although initially interest in the proposal was limited, it sparked the interest of someone else at CERN, Robert Cailliau, who helped Berners-Lee reformat and redistribute the proposal, referring to the system as a "World Wide Web."
By the end of 1990, Berners-Lee had implemented a server and a command-line browser using the initial version of the protocol (HTTP) that he designed for this system. By the middle of 1991, this server and browser were made available throughout CERN. Soon thereafter, the software was made available for anonymous FTP download on the Internet. Interest in HTTP and the web grew, and many people downloaded the software. A newsgroup, comp.infosystems.www, was created to support discussion of this new technology.
By the beginning of 1993, there were about 50 different sites ...