I understand this much but why are they in there 3 times?
Column one:
Administrators

Guests

Users

Moderators
Column two:
Moderators

Administrators

Guests

Users
Column three:
Users

Moderators

Administrators

Guests
Let's say if I wanted to ban any guests from posting, do I check the box next to the guests in all 3 columns or just one? Just wondering what the purpose of having these listed 3 times instead of once.
Sherri