In the practice of Yoga, Asana denotes the art of sitting still and also any posture useful for restoring and maintaining a practitioner's well-being. Additionally it contributes to improving the body's flexibility and vitality, cultivating the ability to remain in seated meditation for extended periods. Such asanas are known in English as "yoga postures" or "yoga positions". Yoga Asana is defined as in form,sitting or standing during an asana while using a posture used in yoga. Modern usage includes lying on the back, standing on the head and a variety of other positions
The history of Yoga Asanas can be traced from Vedic scripture to the modern period, throughout which they underwent successive refinements. Yoga as a discipline was detailed first by Patanjali (BCE 600) in his Yoga Sutras, the first systematized treatise on Yogic theory and praxis. However, a physical culture existed prior to this, and Patanjali's achievement lies in collating all these diverse traditions. The textual evidence indicates that Yoga Asanas have evolved in tandem with the general progress of Indian thought.