The BBS suite implements a hierarchic and sequentially threaded bulletin-board.
Every message lives in both structures.
The BBS runs on the web. You use a web browser to navigate thru the bulletin-board database. I suggest you try the BBS out, as a user would, before you decide to operate one yourself. Log on, leave a message introducing yourself, and browse around and read the messages other people have posted. Who this is for I've streamlined the information storage for the BBS suite in this release, so all the data is stored in the user.bbs table.