My job is to run the website - includes paying for the domain, hosting and everything else. I'm the contact for the hosts - Invision Power, if anything goes down I'm the one who gets it back up again.
Beardy and Wardlelatic are Administrators. They run the forums, which includes creating forums, password resets, and the creative backbone to the site amongst a whole host of other duties that users just don't see - like global moderation. Making sure people aren't spamming, they are posting in the right areas and ensuring we don't have "undesirables" posting trash. These guys also provide financial backing to the board.
Stevie_J, oafcshuck are Moderators. They make sure people aren't spamming in their own forums, they are posting in the right areas and ensuring we don't have "undesirables" posting trash also in their own zones. These lads are pretty good in their field as well, so if somebody posts a query in there - they should pick up the query and offer a response. They have a certain amount of autonomy, they can set their own polls, competitions and things within their forums.
Super Moderators can do the Moderators job in any forum.
Hope this helps...