This list of aircraft carriers of the United States Navy is comprised of every fleet carrier built for the United States Navy. Six separate hull classifications have been used since the Navy's introduction of fleet carriers with the commissioning of Lexington (CV-1) in 1926: they are (CV) - aircraft carrier; (CVL) - light aircraft carrier; (CVB) - large aircraft carrier; (CVA) - attack aircraft carrier; (CVAN) - attack aircraft carrier, nuclear-powered; (CVN) - aircraft carrier, nuclear-powered.