Administrator ==> highest user Auditor ==> Top level users Batch==> internal user Master ==> user used to manage full recovery if needed and can not be removed https://docs.cyberark.com/Product-Doc/OnlineHelp/PAS/13.0/en/Content/PASIMP/Predefined-Users-and-Groups.htm

Administrator - This user appears on the highest level of the User hierarchy and has all possible permissions. As such, it can create and manage other Users on any level on the User hierarchy. Auditor - This user appears at the top of the User hierarchy, enabling it to view all the Users in the Safe. The Auditor User can produce reports of Safe activities and User activities. This enables it to keep track of activity in the Safe and User requirements. Batch - This user is an internal user that cannot be logged onto. This user carries out internal tasks, such as automatically clearing expired user and Safe history. Master - This user has all the available Safe member authorizations, except Authorize password requests, and therefore has complete control over the entire system. This user is used to manage a full recovery when necessary. It cannot be removed from any Safe.

https://docs.cyberark.com/Product-Doc/OnlineHelp/PAS/13.0/en/Content/PASIMP/Predefined-Users-and-Groups.htm