Yin

Yin Yoga combines aspects of Hatha Yoga, the concept of the meridians in Chinese medicine, Taoist philosophy and Buddhist meditation techniques. Yin Yoga has a positive effect on your organs, immune system, muscles and joints. In a Yin Yoga class postures are held for 3-5 minutes, while the muscles are relaxed so that the connective tissue in the body is stimulated.

Yin Yoga combines well with more powerful (Yang) forms of yoga, such as Ashtanga, Anusara and Vinyasa. As a practice, yin yoga is designed to improve the flow of chi (the vital energy of the body) through the energetic channels (or meridians) to improve overall emotional well-being, immunity, and organ health.
When combined with a more active and physical sequence, the practice is then known as Yin Yang yoga. Traditionally, yin and yang are thought of as complementary, not opposite. Thus, balancing the active and relaxing components of your practice can be a good way to create balance and harmony.