What characterizes ashtanga yoga is the dynamic interconnecting postures that create a sense of flow and movement between the static asanas of hatha yoga. There is also a particular type of breathing that is done with each movement. And the movements between the postures are just as important as the postures themselves. Ashtanga yoga posturesa are a series of postures that are always done in the same order and performed with particular breathing patterns. The exact definition of vinyasa is movement synchronized with breath. The purpose of vinyasa is to purify the body by increasing circulation and body heat, leading to an increase in sweating. Vinyasa really facilitates flexibility, and tendon and muscle strength.A good description of Ashtanga Vinyasa Yoga