Power, in the Catholic Church, is centralised and the head of the Roman Catholic Church is the Pope. He lives in Rome in the Vatican City (an independent state over which he rules.)
According to the Roman Catholic Church the powers, given by Jesus to his disciple Peter (who was the first leader of the Christian Church,) have been transferred from Pope to Pope. This transfer of power is called the “ Papal Succession.” This is said to mean that the Pope cannot be wrong (he is infallible) when he makes statements on matters of Roman Catholic belief or morals.
Besides the Pope the Roman Catholic Church clergy is made up of archbishops. bishops and priests. Some bishops and archbishops are also cardinals. Cardinals rank just below the Pope and form what is known as the Sacred College.
This is a group that helps the Pope govern the Roman Catholic Church. On the death of a Pope it is the cardinals who meet, in secret, to elect a new Pope.