Any gymnast swinging from a high bar is performing a Tap Swing.  The proper method for a Tap Swing requires attention to body position:  The body, in its rear-most position on the bar, swings forward in a hollow position.  At the bottom of the swing, the feet remain still, and the upper body continues to swing, creating an Arch.  Quickly, the body returns to a hollow position, and the swing travels forward and upward.  The quick Hollow-Arch-Hollow motion is the Tap.