well there are levels of the church high to low
THEY VOTE DECIDE
1. The Pope -- who is actually a bishop chosen to be the leader of the others; it is an office that he is elected to by the College of Cardinals
2. Cardinal -- also bishops -- but are part of the College of cardinals -- a world-wide group of bishops who advise the Pope on all kinds of things.
3. Arch-bishop -- the head of an arch-diocese. Four arch-dioceses in the U.S. are large enough to be run by a Cardinal -- the arch-dioceses of Boston, NYC, Chicago and L.A.
4. Bishop -- the fullness of the priesthood -- leads a diocese -- a geographic area under his jurisdiction
5. Priest -- serves within the priesthood of the local bishop; Pastors have responsibility for a particular parish within a diocese.