Tanks in World War I
The continued need for four men to drive the tank was solved with the Mark V which used Wilson's epicyclic gearing in 1918. Also in 1918 the French produced the Renault FT, the result of a co-operation between Estienne and Louis Renault. As mentioned before, it had the innovative turret position, and was operated by two men. At just 8 tons it was half the weight of the Medium A "Whippet" but the version with the cannon had more firepower. It was conceived for mass production, and the FT became the most produced tank of World War I by a wide margin, with over 3,000 delivered to the French Army. Large numbers were used by the Americans and several were also lent to the British.
Tank
A tank is an armoured fighting vehicle designed for front-line combat, with heavy firepower, strong armour, tracks and a powerful engine providing good battlefield maneuverability. The first tanks were designed to overcome the deadlock of trench warfare in the 1910s; they are a mainstay of modern ground forces and a key part of combined arms combat. Modern tanks are versatile mobile land weapon system platforms, mounting a large-calibre cannon in a rotating gun turret, supplemented by mounted machine guns or other weapons. They combine this with heavy vehicle armour which provides protection for the crew, the vehicle's weapons, and its propulsion systems, and operational mobility, due to its use of tracks rather than wheels, which allows the tank to move over rugged terrain and adverse conditions such as mud, and be positioned on the battlefield in advantageous locations. These features enable the tank to perform well in a variety of intense combat situations, simultaneously both offensively with fire from their powerful tank gun, and defensively due to their near invulnerability to common firearms and good resistance to heavier weapons, all while maintaining the mobility needed to exploit changing tactical situations. Fully integrating tanks into modern military forces spawned a new era of combat, armoured warfare.