The world wide web (www), like gopher, consists of a network of thousands of server machines, which between them hold documents (called web pages) on virtually any conceivable subject.
A web page is a document which can contain text and graphics for display. In addition to this, a web page can also contain hypertext links, which allow one page to refer to other web pages anywhere else on the network.
In order to access the web you will need a web browser. In general, Linux distributions are not supplied with a web browser so you will need to download one if you want to use the world wide web. Currently, the most common web browser is called netscape, versions of which can be found at several of the main Linux archive sites or one of their mirror sites.
Once you have a copy of netscape installed you will need to start up X-windows in order to run it. When you have netscape running, the front page will be displayed, and one of the boxes on the front page is labeled Location:. This box contains the location of the web page you are currently viewing. Web pages are written in a language called hypertext markup language (html). This uses a simple method for marking sections of the document text as headings or ordinary text, or as links to other web pages or links to other places in the current web page.
Every document available on the web has associated with it a link called its uniform resource locator (URL). The URL for a document has the format:
http://www.server.hostnane/pathnane/on/server
The URL consists of three sections, as follows:
The big attraction of the web and its browsers is that many different protocols can be used in addition to http such as email, news, ftp, gopher and wais.
When you are reading html documents you will find some words highlighted in the text, by color or by underlining. These highlighted words have hypertext links attached to them and clicking on one of them with the mouse will cause the browser to follow the link and display the contents of the document to which the link points.
Just as with ftp and gopher, the world wide web also has search engines available to help you find the URLs of documents related to particular topics. These include:
yahoo http://www.yahoo.com/ lycos http://wwW.lycos.com/ excite http://www.excite.com/ altavista http://altavista.digital. com/ webCrawler http://webcrawler. com/ inktomi http://inktomi/berkeley.edu/
These systems are quite sophisticated in their search strategies. In general, they take a list of keywords from you and search through their databases looking for documents containing as many of your keywords as possible. The documents retrieved will then be put into order according to some relevance criteria and their titles listed to you a small number at a time, usually with a short extract from the start of the document. The listed titles are made into hypertext links to the documents themselves so that you can click on any titles in which you are interested to retrieve copies of your chosen documents.
In addition to running a world wide web client, if your machine will be attached to the Internet full time, it is also possible to run your own web server under Linux. Once again, most distributions do not include a web server but an archie search for cern-httpd or NCSA-httpd will soon locate a copy of one of these two web servers that you can download with ftp and install. Complete installation and running instructions are included in the same tar file that you download for the server software.