Advisor (Metal dots) - The one and only

Administrator (Ruby dots) - Can change EVERYTHING

Supreme Moderator (Red dots) - Can moderate all forums

Moderator (Red dots) - Can moderate one or several subforums, move, sticky, close posts and so on.

Registered (Blue dots, when the bar fills, you get a new title) - A "normal" user that can start new threads, reply to them, read the forums, and simply do anything basic.

Unregistered - Can just view the forum list. An unregistered user will have to register before he can view any subforums, which includes the posts in them.

Banned - Can't do anything at all.

"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram