Catholicism is the traditions and beliefs of Catholic Churches. It refers to their theology, liturgy, morals and spirituality. The term usually refers to churches, both western and eastern, that are in full communion with the Holy See. In 2012, there were more than 1.1 billion Catholics worldwide.
The oldest document that uses the name “Catholic Church” is a letter written by a man named Ignatius. Ignatius lived in the ancient city of Antioch. In the year 107, Ignatius wrote a letter addressed to the Christian community in the ancient city of Smyrna. In this letter, Ignatius encouraged the Christian Community to be loyal to their leader, the Bishop. Ignatius wrote:
“Wherever the bishop shall appear, there let the multitude of the people also be; even as, wherever Jesus Christ is, there is the Catholic Church.”