<< i dont get it... >>
[scooby voice]
Ruh Roh!!
[/scooby voice]
the command man will display applicable info from the "manual pages" for Linux...you should familiarize yourself with the "man pages", they are your friend.
Also, buy a good book on running Linux...O'reilly press has a great one. Also, maybe buy "Linux in a Nutshell" published by O'Reilly...it has a section on rpm and deb package managers.
Also, you can use the gnome package manager to remove unwanted packages...but beware removing the nvidia package, particularly if you have a nVIDIA card installed...there may be consequences.