Many of the world's major religions have their origins in Asia, including the five most practiced in the world (excluding irreligion), which are Christianity, Islam, Hinduism, Chinese folk religion (classified as Confucianism and Taoism), and Buddhism respectively. Asian mythology is complex and diverse. The story of the Great Flood for example, as presented to Jews in the Hebrew Bible in the narrative of Noah—and later to Christians in the Old Testament, and to Muslims in the Quran—is earliest found in Mesopotamian mythology, in the Enûma Eliš and Epic of Gilgamesh. Hindu mythology similarly tells about an avatar of Vishnu in the form of a fish who warned Manu of a terrible flood. Ancient Chinese mythology also tells of a Great Flood spanning generations, one that required the combined efforts of emperors and divinities to control.