āsana आसन Posture and Poise
The term āsana originally stands for a sitting posture which, by definition from the Patañjali Yoga Sutras, should be „comfortable and stable“.
A sitting posture that allows the mind to attain a higher or meditative consciousness. With the emergence of Hatha Yoga various body postures were developed and the term changed from the original seat to various postures with various effects.

āsanas are practised to gain physical strength, to develop more flexibility, to release blockages and thereby develop awareness and consciousness, still with the aim of higher or meditative consciousness.

„Health begins with stability of the body, deepens into emotional stability, then leads to intellectual clarity, to wisdom and finally to the unveiling of the soul.“ – BKS Iyengar

Just as important as the postures in yoga practice is the inner posture, the poise in life practice, to live and act with honesty, decency, loyalty, integrity, sensitivity, compassion, dignity and humility.
Only then it is truly yoga.