Yoga presents the culmination of efforts made by mankind till now control mind and behaviour. It is living science, practiced in an elementary fashion by many in India. While a few perhaps are there who have attained mastery of this science.The background of the derivation and concept of yoga in India is presented followed by a simple exposition of yogic practices and some possible neurophysiologic explanations. Research in yoga will be rewarding as it gives means of exploring and enlarging the functions of the human brain.