Before revision: Watercraft can be grouped into surface vessels, which include ships, yachts, boats, hydroplanes, wingships, unmanned surface vehicles, sailboards and human-powered craft such as rafts, canoes, kayaks and paddleboards ; underwater vessels, which include submarines, submersibles, unmanned underwater vehicles (UUVs), wet subs and diver propulsion vehicles; and amphibious vehicles, which include hovercraft, car boats, amphibious ATVs and seaplanes.
After revision: Watercraft can be grouped into surface vessels, which include ships, yachts, boats, hydroplanes, wingships, unmanned surface vehicles, sailboards and human-powered craft such as rafts, canoes, kayaks ; underwater vessels, which include submarines, submersibles, unmanned underwater vehicles (UUVs), wet subs and diver propulsion vehicles; and amphibious vehicles, which include hovercraft, car boats, amphibious ATVs and seaplanes.