Web - Server

Can any one help im a new to http i dont understand
link below

http://challenge01.root-me.org/web-serveur/ch56/

Many thanks

With this challenge I want you to learn to manipulate http query. So the first thing you need to know is "what is http ? How it works ?". The second thing you need to know is : "How can I see a http request ? What is done when I click on ’Give a try’ challenge button ?"

So work on this way. Don’t forget the goal is to manipulate a http request ? ;)

Good luck :D