This is a really cool form of alternative renewable energy with very specific hydraulic applications. Wave power refers to the energy of ocean surface waves and the capture of that energy to do useful work including generating electricity.
One of the popular devices that uses wave power is a device called an attentuator which is a long, multi-segment, floating structure oriented parallel to the direction of the waves. The fluctuating wave heights along the length of the divide causes flexing where the segments connect and this action is connected to hydraulic pumps or other converters to capture and convert the energy to electricity.
A point absorber is a floating structure with components that move relative to each other due to wave action. It is a floating buoy inside a fixed cylinder. The relative motion of the waves and the buoy are is used to drive electromechanical or hydraulic energy converters.
Wave power is not currently employed widely but has great potential for power generation. Some commercial wave farms have been developed in Europe and one is planned for the coast of California. It does offer manufacturers and distributors of fluid power components an interesting new market opportunity.