All security procedures toward a user are being done through the user's LEVEL and FLAGS. ProBoard can have levels ranging from 0 to 64000, and provides 32 flags (A-Z, and 1-6) that can be ON or OFF.
If a menu needs a certain level and flags, then only the users with a level equal to or higher than that level and with all the needed flags will be able to SEE and CHOOSE this menu option. It will remain invisible to all the other users.
An example will be given in the next chapter.