With the screen "Presence" you can follow up in realtime which persons are present in a certain area. This however requires that you have secured areas available.
When you don't indicate a zone like in the example above ("---") you get an overview of all attendances and absences.
Note: if a person hasn't booked for longer than 8 hours, he will be visualized in red. These are probably the persons who have left the company without booking.