[Dismounted]

Originally Posted by THE UNCEN

What all is in global.php?

global.php instantiates the vBulletin core and associated objects (e.g. database, input cleaner, etc.).

Originally Posted by THE UNCEN

1) Does vB check the passwd in the DB every time a page loads?

vBulletin authenticates using the sessionhash contained in cookies or the URL (when cookies are not available). When the session has expired, vBulletin will check for a username/password combination in the cookies.

Originally Posted by THE UNCEN

2) Does vB store any user data in sessions?

vBulletin does not use "sessions" as you may think of it. It does not use PHP's implementation of sessions, but rather, its own implementation using session hashes and he session table.