Patanjali is often considered the father of yoga. He authored "The Yoga Sutra of Patanjali," which offers almost 200 ways of incorporating the principles of yoga into a person's life.
"The Yoga Sutra of Patanjali" does not offer instructions for stretching or yoga poses. Instead it offers a guide to living a lifestyle filled with morality, Zen and enlightenment. Patanjali was a physician in India and wrote "The Yoga Sutra" somewhere between 200 B.C. and 200 A.D., although the exact time is unknown. His teachings offer an eight-fold path to reach "kaivalya," which means emancipation or ultimate freedom, and is still an important aspect to practicing yoga today.