This view shows the cache of currently authenticated users and the groups exposed by your LDAP server for authentication purposes.
Users that can be cached are created either through "real" logins where a physical user provided a login and password (these end up in the "authenticated" cache) or via internal lookups that are done without passwords (those are cached in the "anonymous" cache). Keeping separate caches for these different kinds of users avoids intermingling and possible privilege escalation because no "anonymous" cached user object will ever be used to perform actions that require real authentication and elevated privileges.
Purge All caches
Every time an authenticated user makes a request to Zope, the username and password are verified. Depending on site traffic and number of users that log in through the LDAPUserFolder this process can happen several times a second. Since a lookup on the LDAP Server can be quite slow, the product will cache the user information for 600 seconds by default. This is the duration of a typical session.