You can find tutorials and examples here:

The Operating System Resource Center
http://www.nondot.org/sabre/os/articles

OS FAQ Wiki
http://www.osdev.org/osfaq2/

Nathan.

Hi,
we are supposed to write a live operating system which is burnt on a CD and can booted on a
computer. This OS should consist of a command-line with these capabilities :
1 – Exploring files and folders which have been burnt on its CD with the minimum commands :
1.1 - “pwd” : printing current directory address.
1.2 - “ls” : printing a list of all files and folders in the current directory.
1.3 - “cd” : changing the current directory to the given one.
1.4 - “cat” : printing contexts of a simple text file.
i do not know how should we start...

Have look on above mentioned links and start cracking case.
Once you get specific questions you are more then welcome to post.

Thread closed