Sailing Yachts (S/Y), also referred as Sailing Boats, are leisure vessels that are equipped with mast/s and sails. The main advantage of Sailing Yachts over Motor Yachts is the fact that they can cross oceans and vast distances without the need to refuel. On the other hand, because of the fact that Sailing Yachts are mainly powered by wind through sails, they are more dependent on weather conditions and offer a slower cruising speed than Motor Yachts. As they have more restrictions in their design (hydrodynamics and aerodynamics), Sailing Yachts usually have smaller dimensions in both height and width and therefore have smaller volumes (compared to a same length Motor Yacht). Sailing Yachts are also often less equipped, especially in their interior space, than Motor Yachts. However, Sailing Yachts are usually less sensitive to sea conditions such as Roll, pitch and Yaw. Two major categories which do not depend on the length of the Sailing Yacht are: Cruising Yachts and Racing Yachts. Navigating, mooring and operating Sailing Yachts is considered more difficult than doing so with Motor Yachts. Therefore the Maritime law gives Sailing vessels priority over Motor vessels. In some countries there is even a separation when licensing a skipper.