...
You can get more information for this group in Users Documentationsection.
Supervisors Group
...
You can get more information for this group in Supervisors Documentation section.
HR Group
Users in human resources group can manage
...
Please keep in mind that giving permission to manage Users/Supervisors group and using existing Jira groups can lead to potential security threat. If you don't want HR users to modify Users/Supervisors groups please disable this option in Admin Configuration for one, or both groups.
You can get more information for this group in HR Documentation section.
Admins
Admin users that are also admins in your Jira.
...
You can get more information for this group in Admins Documentation section.
Technical details
...