Difference between administrators and operators

When I add a user to Event Store I can choose to add the user to one of the groups “Is Operations”, “Is Administrator” or “None”.
What is the difference between the three groups?

Administrators can reset all passwords and all streams. Operations can perform administrative actions (e.g. start/stop scavenge, create/update subscriptions, etc.). Typically you may want to grant Operations access only to such operations and not allow to access regular streams.