The Catholic Church, also known as the Roman Catholic Church, is the world's largest Christian church, with 1.2 billion members worldwide. It is among the oldest institutions in the world and has played a prominent role in the history of Western civilisation. The Catholic hierarchy is led by the Pope and includes cardinals, patriarchs and diocesan bishops. The Church teaches that it is the one true church divinely founded by Jesus Christ, that its bishops are the successors of Christ's apostles and that the Pope is the sole successor to Saint Peter who has apostolic primacy.
The Church maintains that the doctrine on faith and morals that it presents as definitive is infallible. There are a variety of doctrinal and theological emphases within the Catholic Church, including the Eastern Catholic Churches, the personal ordinariates and religious communities such as the Jesuits, the Franciscans and the Dominicans.