Standing, also referred to as orthostasis, is a human position in which the body is held in an upright ("orthostatic") position and supported only by the feet.Although seemingly static,the body rocks slightly back and forth from the ankle in the sagittal plane. The sway of quiet standing is often likened to the motion of an inverted pendulum.Standing at attention is a military standing posture, as is stand at ease, but these terms are also used in military-style organisations and in some professions which involve standing, such as modeling. At Ease refers to the classic military position of standing with legs slightly apart, not in as formal or regimented a pose as standing at attention. In modeling, model at ease refers to the model standing with one leg straight, with the majority of the weight on it, and the other leg tucked over and slightly around.