Play 360 online

I'm sure this is a retarded question but what does it cost to play online? Do you just hook up to a internet connection and play or is it more complicated than that? Thanks
Jerrad

Also, can I get the halo 3 beta and play multiplayer with someone plugged into my 360 or do you have to play that online?

to play online is 50$ a years and is really easy to setup.

i dont have the halo3 beta . so my answer is : maybe, but i doubt it.

Awsome, thanks for the quick reply.