Christianity developed out of Judaism in the 1st century C.E. It is founded on the life, teachings, death, and resurrection of Jesus Christ, and those who follow him are called "Christians." Christianity has many different branches and forms with accompanying variety in beliefs and practices. The three major branches of Christianity are Roman Catholicism, Eastern Orthodoxy, and Protestantism, with numerous subcategories within each of these branches. Until the latter part of the 20th century, most adherents of Christianity were in the West, though it has spread to every continent and is now the largest religion in the world. Traditional Christian beliefs include the belief in the one and only true God, who is one being and exists as Father, Son, and Holy Spirit, and the belief that Jesus is the divine and human Messiah sent to the save the world. Christianity is also noted for its emphasis on faith in Christ as the primary component of religion. The sacred text of Christianity is the Bible, including both the Hebrew scriptures (also known as the Old Testament) and the New Testament. Central to Christian practice is the gathering at churches for worship, fellowship, and study, and engagement with the world through evangelism and social action.