<P> Tanks were an important weapons system in World War II . Even though tanks in the inter-war years were the subject of widespread research, production was limited to relatively small numbers in a few countries . However, during World War II most armies employed tanks, and production levels reached thousands each month . Tank usage, doctrine and production varied widely among the combatant nations . By war's end, a consensus was emerging regarding tank doctrine and design . </P> <P> The tank was invented by the British in World War I, with nearly simultaneous development in France . Tanks of the First World War reflected the novelty of the idea and the primitive state of the automotive industry . World War I tanks moved at a walking pace, were relatively unreliable, and the best usage of them was still developing up to the war's end . A breakthrough in tank design was the Christie suspension: a suspension system developed by American engineer J. Walter Christie which allowed considerably longer movement of the suspension than conventional leaf - spring systems then in common use, and allowed the tanks to have considerably greater cross-country speed . </P> <P> The doctrine of armored warfare changed radically in the inter-war years as armies sought ways to avoid the deadlock imposed by modern firepower and looked for the means to restore offensive power on the battlefield . Initially, tanks had been used for close support of infantry, but as modern mechanized doctrine was developed by several armies, tanks became an essential part of the combined - arms team . In addition to infantry support, tanks fulfilled traditional cavalry roles, provided mobile artillery support, and were adapted to combat engineering roles . </P> <P> Tank design gradually improved in the inter-war period also . Reflecting the growth of the automotive industry, tank engines, transmissions, and track systems were improved . By the beginning of the war in September 1939, tanks were available that could travel hundreds of miles on their tracks with a limited number of breakdowns . </P>

Who had the best tanks in world war 2