A capstan is a vertical-axled rotating machine developed for use on sailing ships to multiply the pulling force of seamen when hauling ropes, cables, and hawsers. The principle is similar to that of the windlass, which has a horizontal axleA mooring is any permanent structure to which a vessel may be secured. Examples include quays, wharfs, jetties, piers, anchor buoys, and mooring buoys. A ship is secured to a mooring to forestall free movement of the ship on the water. An anchor mooring fixes a vessel's position relative to a point on the bottom of a waterway without connecting the vessel to shore. As a verb, mooring refers to the act of attaching a vessel to a mooring