New to FB fan pages, could use a little help.

So the main thing I an looking to do is add more pages to the fan page.

I have seen it where people have made more sub pages that have custom links on the right.

So something like this.
http://www.facebook.com/pages/hCG-Diet-Supply/127968157234899?sk=app_342349437729

This one has to do with shopping but I have seen others just have big ads.

So I guess here are the things I would really like to know.

1: What should I call these pages?
2: How can I make one?
3: What are the limits? (html, css, php*I wish*, java)?
4: Anything else I may be for getting to ask.