Restricted area

[eluser]solid9[/eluser]
As far as I know.
The common way is to create a table called users_groups and groups.

You can use the GROUPs table as reference

Code:

ID | Name   | Description
-----------------------------
1  | Admin  | Administrator
2  | Normal | Ordinary member
3  | Gold   | Gold member

And you can use the users_groups table as junction table.

As InsiteFX said you can create a method to restrict a user.