A frigate is a type of warship that came into common use in the 17th and 18th centuries. Frigates began as warships that were too small to stand in the line of battle and were designed for speed and agility. As the type developed in the 18th and 19th centuries, they became used for scouting, escort duty, maritime patrol, and commerce raiding. With the advent of steam power and ironclads, the frigate was largely replaced by newer ship types.
A sailing frigate was a ship-rigged (three masts, square sails) vessel that mounted its primary battery on one deck. This armament was often supplemented by additional guns on the topmost deck. Frigates typically mounted 28 to 50 guns.
The term frigate is still used by some navies to refer to smaller, lighter warships which typically perform escort, anti-submarine, or anti-aircraft roles.