Although it was not the most powerful tank made during the Second World War, the M4 Sherman was the epitome of the American fighting spirit during the time period-- maneuverable, fast, and mass-produced.
Over 50,000 M4 Sherman tanks were produced in seven different varieties in almost every allied country-- Canada produced the Ram II, while Great Britian produced a model with a 17 pounder cannon.
The standard M4 Sherman was equipped with a 75mm cannon, able to pierce through most lightly armored vehicles and tanks. It was no match for the sturdily-built Tiger and Panther tanks of the German army, which had much more powerful cannons and thicker armor.
The engine of the M4 was originally built by the Wright corporation, but, as the M4A2 and M4A3 varieties were developed during 1942-1943, the M4 was fitted with a GM diesel engine, and then later a Ford V8-- the most common variant.
As the war progressed, the M4 was upgraded to a 76mm cannon complete with a higher gun velocity. Some varieties also came with a much larger and more powerful 105mm Howitzer cannon.
The M4 first showed its battle prowess during America's (led mostly by Patton), campaign in North Africa during 1942. The Tiger and Panther tanks were not yet in full production, so the M4 fared very well against the earlier German tanks, the Panzerkampfwagen III, a light infantry support vehicle, and the Panzerkampfwagen IV, the German light/medium mainstay battle tank. The M4 was well suited to desert combat, and helped the allies push the axis out of North Africa.
America's Sherman later saw action in the invasions of Italy and Sicily in 1943 and 1944, where its maneuverability in tight urban and suburban areas gave it a slight edge over the more cumbersome German tanks.
However, the M4's most popularized role was its contribution to the D-Day invasion of Normandy in 1944, where amphibious Shermans drove ashore and help break the static German defensive positions. They were crucial in the breakout of the initial beachhead, and later proved very effective in the French hedgerows. The M4 was also heavily used in the rest of the liberation of France and throughout the drive to the Rhine-- it remained America's sturdy main battle tank throughout the war.