this document is taken from the "cité des Sciences" with FEDER and translated into English. It explains the URL.

1. What is a URL?
Summary
The URL (Uniform Resource Locator) is the address of the website or webpage . It locates this site
hosted by a web server on the World Wide Web . The address goes from the most general to the most
specific. This system is a tree where each element is included in another like a Russian doll.
• The IP address is used in a dialogue between computers to identify the sender or recipient and route
information correctly. An IP address consists of numbers. This is the address behind the URL and
identifies the Web server that hosts the site.
• Domain Name Server (DNS) helps give the equivalent words of an IP address. It is easier to remember
a name than a series of numbers.
Ex: IP = 213.228.0.42 www.famille - declic.fr
You can type in the IP address in your browser.
• The client / server principle is the basis of the Internet. A server is a computer that provides resources
to computers "customers." As a web user, the web send your requested pages .