Back distinguishes between two main types of users - experts and requesters.
Expert is usually a member of one of the business teams, who is receiving and working on requests from employees. They have an account with Back and therefore can log in to the expert interface.
Requester is someone who submits requests to Back, but is not receiving and wokring on requests. This would be most of your employees from other departments.
⚠️ Only experts need to be explicitly invited into the system! By default, requesters only have a "user profile" that is created automatically once they create their first request or when we fetch their information from your Slack organization.