To bend the knees in the most comfortable manner. to assume or maintain a position in which the body is supported on the feet (
heels down) and the knees are bent so that the buttocks rest on or near the
heels.
American Toilets make people squat with their
heels up. After about 30 years, people can hardly perform the other way to squat.
To begin learning how to correctly squat, one must "hold on to something for dear life".