Can anyone help me with what a "user" is and how many

[Jim Collins]

I am trying to understand how many users I need. I have internal developers and managers but I also have external customers that need to enter issues and also participate in Project Plans. So far JIRA looks good but not having anyone to speak to or help is quickly taking off the radar.

[Nic Brough -Adaptavist-]

A user is anyone who logs in so that they can view, create and edit issues.  At a glance, all your people in the question need to be "users".

There are types of users which could affect your numbering though:

• Core users have access to the basics of JIRA - projects and issues.
• If you have JIRA Software, then Software users have Core access, plus access to Software boards (Scrum and Kanban)
• If you have Service Desk, then Service Desk agents can run Service Desk project, as well as have Core access
• If you have Service Desk, then Service Desk customers have a simple basic portal interface - they can raise calls, which JIRA users and Agents other users see as JIRA issues, but they can NOT see the rest of JIRA.

 JIRA Software users cost a bit more than Core users.  Agents cost a LOT more than other users.  Customers are free - you don't need a licence for them.