A user is anyone invited into the event via email and assigned a permission. If the crew member needs to do any of the functions listed below then they must be a user:
They help build out the rundown or game script
They make contributions/notes to department columns
They create Shows, Schedules, or Lists.
They upload files to the event
They follow along with the showcaller
They need access to all show files and docs on the event
They modify event settings
They organize show content
...
If you would like a deeper view of our User permissions you can read up on that here.
If a crew member needs none of the above functionality and only needs the ability to see the rundown, then they could be given a Guest Pass link. You can read more about that here.