Christianity is the largest religion in the world. Its members are split between Catholics, Protestants and Orthodox Christians, although there are literally thousands of sub-sects each with their own ideas about how Christianity should manifest itself.
Christianity takes its name from Jesus Christ, but the religion is based to a large degree on the writings of the apostle Paul, some of which constitute several books of the New Testament. The religion is based on the Bible.
"There ought to be a term that would designate those who actually follow the teachings of Jesus, since the word 'Christian' has been largely divorced from those teachings, and so polluted by fundamentalists that it has come to connote their polar opposite: intolerance, vindictive hatred, and bigotry." —Philip Stater