What a user is depends on the context of your use-case. In general, we consider a user to be a person who actively makes use of the Surfly API and has an account. Therefore, for example, a customer who contacts your helpdesk and starts a co-browsing session from your website is not a user. But the agent who has a Surfly account and takes the call, is a user.
Surfly’s license is user based. This means that while any seat can create an unlimited number of sessions, each seat is to be used by a single user. Sharing a single seat over multiple users is not allowed.