Question: what is the difference between raja yoga and kriya yoga?
Answer: Raja Yoga works in more subtle levels. It involves Pranayama, the movement of prana up and down the spine, the chakras, Kundalini, also the tenets of self-control etc. Kriya Yoga may be said to be a part of Raja Yoga, but it is a very dynamic practice. ... It does contain an asana from Hatha Yoga and a hand mudra too.