Users and Groups Each AccuRev user must have an AccuRev username (also called a “principal-name”). AccuRev maintains its own user registry, which is separate from the registry maintained by your machine’s operating system (or the network). Optionally, you can create AccuRev user groups, and add users to the groups as “members”. Starting in Version 4.5, groups can be nested within one another; that is, a group can be a member of another group. AccuRev groups are independent of operating system groups. Groups are used by the ACL facility to grant or deny access to a particular resource for an entire set of users. They are used by the Locks facility to specify a set of users to which a stream lock does or does not apply. (See Locks on Streams and Access Control List (ACL) Permissions.) Usernames and Groupnames Each AccuRev group has a user-defined name. Usernames and group names share a “namespace” in AccuRev. This means that a user and a group cannot have the same name.