There are many different surfboard sizes, shapes, and designs in use today. Modern longboards, generally in length, are reminiscent of the earliest surfboards, but now benefit from modern innovations in surfboard shaping and fin design. Competitive longboard surfers need to be competent at traditional "walking" manoeuvres, as well as the short-radius turns normally associated with shortboard surfing. The modern shortboard began life in the late 1960s and has evolved into today's common "thruster" style, defined by its three fins, usually around in length. The thruster was invented by Australian shaper Simon Anderson.