A main battle tank (MBT), also known as a battle tank or universal tank, is a tank that fills the armor-protected direct fire and maneuver role of many modern armies. They were originally conceived to replace the light, medium, heavy and super-heavy tanks. Development was spurred in the Cold War with the development of lightweight composite armour. They are still supplemented in some armies with light tanks. Not all armored, tracked military vehicles are tanks and are designed for other battlefield roles.