In parallel to the diocesan structure are a variety of religious institutes that function autonomously, often subject only to the authority of the pope, though sometimes subject to the local bishop.
The Catholic Church teaches that it is the One, Holy, Catholic and Apostolic church founded by Jesus Christ in his Great Commission, Of its seven sacraments the Eucharist is the principal one, celebrated liturgically in the Mass.
The church teaches that through consecration by a priest the sacrificial bread and wine become the body and blood of Christ.
The pope exercises a direct patriarchal role over the Latin Church, which is considered to form the original and still major part of Western Christianity, a heritage of certain beliefs and customs originating in Europe and northwestern Africa, some of which are inherited by many Christian denominations that trace their origins to the Protestant Reformation.
The Eastern Catholic Churches follow the traditions and spirituality of Eastern Christianity and are Churches that have always remained in full communion with the Catholic Church or who have chosen to reenter full communion in the centuries following the East–West Schism and earlier divisions.
The largest and most well known is the Latin Church, with more than 1 billion members worldwide.
Relatively small in terms of adherents compared to the Latin Church, are the 23 self-governing Eastern Catholic Churches with a combined membership of 17.3 million as of 2010 The Latin Church is governed by the pope and diocesan bishops directly appointed by him.
The name "Catholic Church" for the whole church is used in the 1990 Catechism of the Catholic Church, the 1983 Code of Canon Law, the documents of the 1962-65 Second Vatican Council, and numerous other official documents.
"I will give you the keys of the kingdom of heaven, and whatever you bind on Earth shall be bound in heaven, and whatever you loose on Earth shall be loosed in heaven." Jesus to Peter in the Gospel of Matthew, The crossed gold and silver keys of the Holy See symbolise the keys of Simon Peter, representing the power of the papal office to loose and bind.
The triple crown papal tiara symbolises the triple power of the Pope as "father of kings", "governor of the world" and "Vicar of Christ".