What is the World Wide Web?

The World Wide Web is a network of computers that serve webpages. The World Wide Web is a major component of the Internet, along with email, usenet, ftp, and some other minor protocols. The term "world wide" refers to the global nature of the World Wide Web, and the term "web" refers to the interlinking of documents by means of hypertext. In simple terms, this means that documents on the Web (or WWW for short) can reference, or link to, other documents by simply stating on which machine they reside, and where on that machine. Computers that serve documents on the World Wide Web are called servers, and the programs used to connect to servers and to display webpages are called web browsers.

Documents on the World Wide Web are traditionally written in HTML, a major component of the web. HTML defines the appearance and content of a webpage, and usually links to other HTML pages via a Uniform Resource Identifier or Uniform Resource Locator (URL). The pages are transferred between computers via HTTP, the HyperText Transfer Protocol. The most familiar of these concepts is without doubt the URL, such as "http://what-is-what.com/what_is/world_wide_web.html". The first part: "http://" means that the document should be fetched using the HTTP protocol. The next part, "what-is-what.com/" is the name of the server on which the document resides. The last part: "what_is/world_wide_web.html" means that the document named "world_wide_web.html" resides in the "what_is" folder. Note the suffix ".html". Usually, file name extensions indicate in what format the file was written. In this case, the file is written in HTML. This is expected, as the file is meant to be accessed on the WWW.

The history of the The World Wide Web dates back to 1980. In that year Tim Berners-Lee, a physicist at CERN (the European Organization for Nuclear Research), devised a way for moving documents between remote computers. The proprietary system, named ENQUIRE, went through several monumental changes between 1980 and its public release in 1991. The physicists at CERN were in need of a simple way for non-computer literate scientists to exchange data between laboratories very far apart. Thus, a simple to learn language for creating documents in outline format was invented, called HTML. In order to transfer the documents between computers, a simple text-based protocol was needed, thus HTTP was invented. The computers that understood HTTP requests and served HTML documents in response were called servers, and the programs used to actually view the documents were called browsers. As the system of requesting and viewing documents could be used by a computer anywhere in the world by any compliant computer connected to a phone line, the system was called the World Wide Web.