On the web

World Wide Web

For 20 years, people have been able to travel all around the world through virtual paths called "The Internet". Electric wires transport digital information, and these wires look like a huge web which covers the earth.

This situation explains why the commonly given name for the Internet is World Wide Web or www.


But the WEB is just a small part of the Internet. There are a lot a services which use the Internet :


The purpose of the www is to broadcast documents and information. They are visible on webpages.

Webpages


A webpage is a document written in a HyperText Markup Language (HTML) and displayed by a web browser.

The HTML code is stored in a web file placed on a computer or on a web server.


A webpage includes :

Each element in the page, is delimited by tags. They compose the HTML language.













Data transfer


When a user is on the internet, the computer which displays the web pages is called the client, and the one which sends the code is the server.


From the server to the client

The access to the web pages (on a web site) is possible thanks to the internet address. Sometimes it's called : URL : Uniform Resource Locator


An address is composed by :


There is ponctuation between each part of the address :

For example : http://www.entea.fr


Then, folders and web filesnames must be specified.

For example : http://www.siloged.fr/cours/ADNA_HTML/index.htm


IMPORTANT :

There are a lot of reserved characters on the web. It's better to use only letters and numbers in the filenames and folder names.


From the client (web designer's computer) to the server

To store web files on the server, the webmaster needs a software which establishes a connection to the server (Filezilla is the a famous one).

He also needs the

  1. host of the web site : file transfer address;
  2. login name;
  3. the password which protects the web site from the hackers;
  4. The port number for a file transfert protocol is 21


After these setups, the connexion will be effective and the webmaster can store the files on the web site.