Activity Active - can be applied if moderator keeps on a regular basis with the wiki, regardless if moderating or doing what normal users do. This means that the user talks in forum/makes edits and pages often, responds to messages on message wall pretty quickly and checks notifications, eventually responding.
Semi-Active - is applicable if the following moderator does not check the wiki as often as others, but still does his job, produces pages and responds to messages, just more rarely.Inactive - applies if following moderator shows up on the wiki rarely. This means that the user infrequently deletes pages/threads, creates pages, makes edits or discusses in forum. It also takes longer for response in inactive's users message walls and/or mentions.
Permissions
Thread moderator's permissions
Apart from what a normal reader and editor could do, users with thread moderator status will be able to do:
Edit posts on forums and article comments;
Change categories of posts;
Delete posts and article comments;
Lock posts.
Content moderator's permissions
Apart from what a normal reader and editor could do, users with content moderator status will be able to do:
Protect and unprotect pages;
Revert many edits at once;
Edit protected pages;
Delete/undelete pages, files and templates.
Administrator's permissions
Apart from what a normal reader and editor could do, users with admin status will be able to do:
Block users;
Change the wiki theme;
Edit wiki CSS;
Promote to thread moderator (promoting to content variant is restricted to bureaucrats or higher);
Do everything that thread and content moderators can do.