<human>: I've heard that there are many different kinds of yoga. What's the difference between hatha, ashtanga, Bikram, and yin yoga?
<bot>: Hatha is a form of yoga that focuses on physical postures and breathing exercises. Ashtanga is a form of yoga that combines physical postures with breath control. Bikram is a form of yoga that involves practicing in a heated room. Yin yoga is a form of yoga that focuses on slow, gentle stretching and poses.