Users are the people who have been granted access to the account.  

Each user must be give a unique login.  

The email can be duplicated amongst multiple users if needed.  

A master user can create and edit other users and view the user history for a user.

If a user is assigned a group, then they will only be able to view/edit the other items that have been assigned to that group and the items that have been assigned to "All Groups".  The items are vehicles, zones, recipients, and all alerts.

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