Besides the different ranks given for a certain post count, which i wont reveal, there are the forum ranks/groups.
Leaders: That's me, I'm the boss, simply put.
Co-Leaders: Help me out with the forum and clan wide decisions.
Global Moderators: Moderators with access to the whole forum, they can edit just about everything.
Moderators: Trusted members that are assigned to moderate either one specific forum, or a specific section.
Captains: Officers of the K Divisions. Have mod powers in the K Divisions.
Full Member: Have access to all the relevant forums for a member. And can also fully control their posts, editing them, etc. etc.
HopeFulls: Not as much access as a member, but almost. They cant do some basic things, like edit their posts in certain forums.
F.N.G: Fucking New Guy
Not much access to the forum, and not as many features availble to them.
Forum Applicant: Not technically a member yet, but still with some degree of forum access, to allow posting.
Game Applicant: Has as much access to the forum as a Guest, so not very much. They're being tested on their game, not their forum activity, in this rank, so that's why.
Guest: Can only see what you see before you log in.
So as you can see, the higher rank you are, the more of the forum you can see. And before you reach Full Member status, You've not seen the full forum yet, which is quite vast.