Shat Karma Kriyas or Shat Karmas are six purification techniques that pertain to Hatha Yoga.
Ha-tha is the path of practice and purification - internal, as well as external. It is therefore an additional Yoga path to the four traditional paths. Regular practice of these exercises requires willpower and discipline and that is why this path is called Hatha Yoga.
Ha-tha, also means sun and moon. This refers to the union and harmony of the sun and moon principles, which result from the practice of Hatha Yoga.