In t'ai chi ch'uan, pushing hands is used to acquaint students with the principles of what are known as the "Eight Gates and Five Steps," eight different leverage applications in the arms accompanied by footwork in a range of motion, intended to allow students to defend themselves calmly and competently if attacked. Also known as the "13 original movements of tai chi", a posture expressing each one of these aspects is found in all tai chi styles. Training and pushing hands competitions generally involve contact but no strikes.