The Tank, Cruiser, Ram was a cruiser tank designed and built by Canada in the Second World War, based on the U.S. M3 Medium tank. Due to standardization on the American Sherman tank for frontline units, it was used exclusively for training purposes and was never used in combat.

Due to the loss of the majority of the United Kingdom's tank force in France, tank production in the UK at the start of the war was insufficient to supply Canada as well, so it was decided to manufacture locally. The Montreal Locomotive Works, which was a subsidiary of the American Locomotive Company, was designated the Canadian Tank Arsenal. Initial production was of Valentine tanks, many of which would be supplied to the USSR. Although the Valentine used a number of US produced parts, limitations in the availability of armour plate affected Valentine production.

The Canadians were interested in production of the M3 Medium. However the M3 design lacked a turret for its main armament. The British Tank Mission, which was involved in the modifications of the M3 for British use, contributed a tank expert to design a new hull that could take a larger turret while retaining the lower hull of the M3. The new hull was cast rather than welded or rivetted and lower than that of the M3.

Ram, ram, or RAM may refer to:

A tank is a tracked, armoured fighting vehicle designed for front-line combat which combines operational mobility and tactical offensive and defensive capabilities. Firepower is normally provided by a large-calibre main gun in a rotating turret and secondary machine guns, while heavy armour and all-terrain mobility provide protection for the tank and its crew, allowing it to perform all primary tasks of the armoured troops on the battlefield.

Tanks in World War I were developed separately and simultaneously by Great Britain and France as a means to break the deadlock of trench warfare. Their first use in combat was by the British Army on September 15, 1916 at Flers-Courcelette, during the Battle of the Somme. The name "tank" was adopted in Great Britain during the early stages of their development, as a security measure to conceal their purpose (see Etymology).

Tanks of the interwar period evolved into the designs of World War II. Important concepts of armoured warfare were developed; the Soviet Union launched the first mass tank/air attack at Khalkhin Gol (Nomonhan) in August 1939, which later resulted in the T-34, a predecessor of the main battle tank; this was quickly followed up by Germany on a larger scale when they introduced blitzkrieg ('lightning war') less than two weeks later; a technique which made use of massed concentrations of tanks supported by artillery and air power to break through the enemy front and cause a complete collapse in enemy resistance and morale.