Administrators and Moderators
Any group on Gaggle Mail has at least one administrator, this is usually the person who created the group but you can add as many administrators as you like. Administrator's are usually but don't have to be a member of the group.
Administrators are the only people who can; add, edit or remove members, change groups settings, add or remove other administrators, and access other member's settings. If moderation is enabled, administrators can also moderate messages.
An administrator can make an existing member an administrator by selecting them on the Members page, then checking the Administrator checkbox. If moderation is enabled, you can make an existing member a moderator in a similar way by clicking the Moderator button.
If you'd like to make a non-member an administrator, you can do this by inviting them from the Settings area. Moderator's who are not member's of the group can also be invited from the Moderation area.