Site Owner
Some guy.
Administrator
A top-level site manager who can make changes to content types, categories, user titles, and site settings.
Staff
A paid employee of the company.
Moderator
Moderators can respond to user reports and can delete and edit posts by other users.
Developer
Part of the development team for the website.
Author
A user approved to post articles directly.
Contributor
A user who has made a post or thread that was featured as an article.
Quality User
An arbitrary title given to quality users.
Classic User
A user who has an account. Borat-very-nice.mp4.