It's just a little question:

What's the difference between a forum, a topic, a thread and a board? :???:

board - I believe this refers to all the forums, but it may be used to refer to a catagory of forums
forum - a section of the board - "Level Designing", "Technical Help", etc
thead - a section of the forum - "Just a little question...", "School's starting again!"
topic - the title of a thread

Thanks! :D