The forums? Basically the forums are a chat room type thing, with a more email/comment type format. Think wiki, but the replies are more organized and easier to sort through.

When peole reply to your posts, specifically, you get a notice, meaning you don't have to sift through all the other comments, although you can if you really want to. It's nice.
At least on this site it's that way.

Forums generally go: Main Category -> Sub Category -> Topic -> Posts. Although sometimes you have multiple subtopics.
It's an organized way to chat, because in specific subtopics that's what you talk about. Nothing else. And since we're small there's no spamming and messed up stuff to get in the way.

Hope that helps. Any more questions, just ask.