Governing Mayor of Berlin

The Governing Mayor of Berlin (German: Regierender Bürgermeister von Berlin) is the mayor, head of state, and head of government of Berlin, presiding over the Berlin Senate. As Berlin is an independent city as well as one of the constituent states of Germany (Bundesländer), the office is the equivalent of the ministers-president of the other German states (except those of the other two city-states, Hamburg and Bremen, where the heads of government are called "First Mayor" and "President of the Senate and Mayor", respectively).

Source: Wikipedia — Governing Mayor of Berlin (CC BY-SA 4.0)