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What is it$?$

The World Wide Web is one of the newer information gathering services on the Internet (early to mid 90s). It is also the most successful tool, by far, used to access information. It is based on the concept of hypertext, first developed at CERN (Centre Européen de Recherche Nucléaire), the European particle physics lab in Geneva, Switzerland..

A hypertext is based on the concept that a word, phrase, or object is actually a link to another object. The hyperlink object is usually either underlined, highlighted, or of a different colour.

The link could represent many types of objects. When the link is activated (by clicking the mouse of a graphical browser, or pressing the ENTER key on an ASCII browser), a number of different scenarios may happen.

Table 1.9 displays the different actions the browser may take, depending on the type of link.

It is assumed the example browser being used is graphical in nature (eg: netscape).


Table 1.9: Some actions taken by WWW browsers.
linked object action or program used
Local text file File is displayed.
Remote text file File downloaded, then displayed.
Remote HTML file File downloaded, then interpreted.
Remote PostScript file File downloaded; ghostview invoked.
Remote GIF file File downloaded; xv invoked.
Remote audio file File downloaded; sfplay invoked.
Remote video file File downloaded; mpeg_play invoked.
Remote DVI file File downloaded; xdvi invoked.
Telnet session to host xterm invoked with telnet host.
Gopher site Gopher site contacted; gopher menu started.
FTP site FTP connection done; file may be downloaded.


The language used to write WWW documents is HTML (HyperText Markup Language).

http (hypertext transport protocol) is the protocol used to access/service HTML documents.


next up previous contents
Next: netscape, internet explorer, lynx, Up: WWW: World Wide Web Previous: WWW: World Wide Web   Contents
Claude Cantin 2010-10-24