CrossFit is a strength and conditioning program consisting mainly of a mix of aerobic exercise, calisthenics (body weight exercises), and Olympic weightlifting.
The ultimate goal of Yoga is moksha (liberation), although the exact form this takes depends on the philosophical or theological system with which it is conjugated.
Stretching is a form of physical exercise in which a specific muscle or tendon (or muscle group) is deliberately flexed or stretched in order to improve the muscle’s felt elasticity and achieve comfortable muscle tone.