A Google Group is a convenient way for a group of people to communicate together without having to expose individual group members email addresses. Only email addresses registered within the group may send and receive messages via the group. Google groups are set up under Gmail accounts. Each group has a single Gmail account owner, but may have multiple managers, which must also must be a Gmail account, that may add and delete individuals to and from the group. Non Gmail addresses may be added to the group, but may not be managers. There may be multiple groups per owner.