Someone with Manager Permissions who has ultimate privileges/control over your Organization. By default, the person who creates the Organization is automatically an Account Owner. You can have as many Managers as you like. Generally speaking, you should make trustworthy supervisors Managers in order to take the burden off any single person. (How do I designate additional people as Managers? Check out this article.)
A non-comprehensive list of privileges only Managers have
Breakroom as a Crew App Alternative
Breakroom as a Slack Alternative
Breakroom as a When I Work Alternative