no follow use?

[nlbrt]

Hi all,

I have been told to use the no follow tags... i have a couple of questions about this.

1) how does this work?
2) where should one implement this and why?
3) If one doesnt vs Does what kind of a Ranking difference is one looking at?
4) How does one implement this?
5) anything else that needs to be implemented with the nofollow command?
6) what exactly is the command itself "ie" "no=follow" etc

Thanks