Brig
From PotC Wiki
A brig was a sailing ship with two square-rigged masts, one fore, one main. During the Age of Sail, brigs were seen as fast and maneuverable and were used as both naval war ships and merchant ships. Their use dated back to before the 1600s.
The main mast of a brig was the aft one. To improve maneuverability, the mainmast carried a small fore-and-aft sail (also called a gaff sail). Brig sails were named after the masts to which they were attached: the mainsail; above that the maintopsail; above that the main topgallant sail; and occasionally a very small sail, called the royal, above that.
The word "brig" had been used in the past as an abbreviation of brigantine (which was the name for a principally fore-and-aft two-masted rig with a square rigged foremast). The brig actually developed as a variant of the brigantine. By re-rigging a brigantine with two square sails instead of one it gained greater sailing power.
