Maharishi Patanjali, called 'father of yoga', authored classical book 'Yoga Sutras'. It's believed he was born in BC era in UP's Gonda and later shifted to Kashi. As per beliefs, he was incarnation of 'Sheshnag'. Credited with documenting yoga, he presented 195 yoga sutras. He advocated eight-fold path of 'Ashtanga Yoga' (yama, niyama, asana, pranayama, pratyahara, dharana, dhyana and samadhi).