Attribute groups sole purpose is to group certain attributes together to make them easier to navigate within the Attribute Library.
Attribute Group Administration enables groups to be added / removed, and for attributes to be assigned to these groups.
When a group is selected, dragging or double-clicking any attribute from the unassigned list into the Attributes in Group box.
Similarly, attributes can be removed by reversing the process.
To delete a group, highlight it and press the "Delete" button. All attributes from within that group will then be moved to the unassigned list.