In this directory, you can see what relationships exist between users and groups. It is not possible to edit the relationships at this point. For relationship configuration, see 11.2.8 The "Properties…" Dialog: The "Relationships" Tab.
Example:
Users of the group "Group A" signal user "User A_2" about their status. Conversely, user "User A_2" signals his status to all users of the group "Group A".