Messaging is the primary function of the BBS. Messages include public messages, private mail, and files.
The BBS comes with one generic message stack. For each message category you have, you'll need to make a copy of this stack and rename it.
Messages in the message stacks can have files "attached" to them, and they can be marked "private." Therefore, all three functions of public messages, private mail, and files are handled by this one structure -- this is different than most other BBSs, which separate all or some of these functions.