What is a Squat?

The squat is a fundamental movement of life. An inability to effectively squat severely limits our functional ability and ultimately may predispose one to developing an array of ankle, knee, hip and back problems.
I believe a squat can be defined as any movement where one flexes through the hips, knees and ankle. While the squat appears to occur primarily in the sagittal plane of movement, the movement available at the spine, hips, knees and feet/ankle usually involves all three planes (sagittal, frontal and transverse) of movement.