User groups are used only when you've had a custom-built application made for you by Hidden Colour. They are used to contain sections of users and allow a particular admin user to only see information relating to that user group.
To change a user's group:
1. Select a user to change, as you would for the standard Edit User procedure.
2. Then select the Groups tab and the form displayed below will appear:
3. To add this user to a group, select the group from the Add user to drop-down menu, then click Save Changes.
To remove this user from a group, click Remove next to the group line that you wish to remove.