Two-master is a type of sailing vessel that has two masts. A KETCH is a two-masted sailing vessel with the aft mast stepped forward of the main mast. A BRIG is a two-masted sailing vessel with square sails on both masts. A YAWL is a two-masted sailing vessel with the aft mast stepped aft of the main mast. A brigantine is a two-masted sailing vessel with square sails on the foremast and fore-and-aft sails on the mainmast.