The Canon 200mm f/2 L USM IS is a high-performance, telephoto, L-class prime lens with USM autofocus and IS image stabilization. This lens is outstanding for photography in available-light situations, including weddings, indoor sports, theater, fashion and candids.
Fast Aperture: The large aperture of this lens helps give you fast shutter speeds in available light and excellent depth-of-field control.
USM: Canon USM ultrasonic autofocus is faster and quieter than mechanical autofocus systems.
IS: Canon IS image stabilization helps to steady your pictures and reduce blur from camera shake.