A surfboard is a narrow plank used in surfing. Surfboards are relatively light, but are strong enough to support an individual standing on them while riding an ocean wave. They were invented in ancient Hawaii, where they were known as papa he'e nalu in the Hawaiian language, and were usually made of wood from local trees, such as koa. They were often over 460 cm (15 ft) in length and extremely heavy. Major advances over the years include the addition of one or more fins (skegs) on the bottom rear of the board to improve directional stability, and numerous improvements in materials and shape.
