In Yin Yoga we hold the postures for a longer period of time in order to stimulate the connective tissue of the body such tendons, fascia and ligaments.
Yin yoga is based on the Taoist concept of yin and yang, two aspects of the same nature.
Yin is the stable, immobile, cold, passive state. Yang is the changing, mobile, hot, active state. As a consequence it improves blood circulation and flexibility through a calm investigation of our body and mind achieved by passive asanas.