Though āsanas are a very popular mode of exercise, the word ‘āsana’ has a much wider connotation and deeper signi-ficance. Patañjali, the great master of yoga, has listed āsana as the third of the eight steps of yoga. According to him, any posture in which the yogi can sit steadily and comfortably, is ‘āsana.’ This āsana can be mastered through meditation on the infinite and by a relaxation of the body and mind. When this technique of āsana is perfected, the yogi acquires immunity from the effects of pairs of opposites like heat and cold, hunger and thirst, happiness and misery (vide Yoga-sūtras 2.46, 47 and 48). Out of the six āsanas that are recommended as suitable for meditation, padmāsana and svasti-kāsana are supposed to be the best.
Āsanas as physical postures come under the purview of another branch of yoga, known as ‘Haṭhyoga.’ These āsanas, it is claimed, can cure diseases, improve health and help in meditation. Though the typical posture of every living being can serve as a model for an āsana, only 84 āsanas are handed down in tradition as especially suitable for human beings. Out of these again, only 32 are more in vogue.
Āsana can also mean a seat. Various kinds of seats have been recommended as suitable for meditation. Seats made of kuśa grass, deer-skin, tiger-skin, woollen rug or silk cloth have been mentioned in the works on yoga, along with the fruits one will get by using them.