The earliest known figure of Taoism in ancient China is Lao Tzu, the legendary author in the 5th century B.C.E of the Tao Te Ching or "Classic of the Way [Tao] and Its Power." The Tao is the formless and infinite origin of all things. Taoism became both a philosophical school and an organized religion, with orders of priests serving the people of China through their knowledge of deities, rituals, and divination.