Breath of Fire is a pranayama technique which involves quickly pulling air in and out of the lungs in a very rhythmic motion. Most teachers suggest that you put your right hand on your belly and push your belly out on each of the quick exhales so that you can stay in the rhythm. This pranayama is often used during Kundalini yoga classes and you can definitely feel the energy that is stirred up and moved around the body with this technique. Breath of Fire is said to charge the nervous system and purify the blood. If you want to try Breath of Fire, watch this YouTube video which demonstrates the technique for beginners, intermediate and advanced students.