HATHA YOGA, a basic form of Kriya Yoga, is the yoga of physicality, asanas, and movement. It is conceivably the most well-known form of yoga in the West; however, the main classical text on yoga - the Yoga Sutras of Patanjali discusses physical asanas (Hatha Yoga) in only three of its two hundred verses.
Hatha Yoga Asana Definition
ASANA - A Sanskrit word for ‘seat’: a physical posture (see also anga, mudra); the third limb (anga) of Patanjali’s eightfold path (astha-anga-yoga); originally this meant only meditation posture, but subsequently, in Hatha yoga, this aspect of the yogic path was greatly developed into exercise positions.