What does the Sherman tank have in common with a Porsche 911? They're both rear-engined. But let's start with the tank's proper name, the M4.
M signifies Medium, as opposed to Light or Heavy, the other sizes tanks come in. The M4 got its nickname because the British liked to call their U.S.-supplied tanks after generals from the American Civil War. There was a Grant and a Lee before this one. Anyway, the nickname stuck, as they often do, and soon it was being referred to as a Sherman on both sides of the Atlantic Ocean.
Construction of the Sherman started in 1941 and the first examples saw action in El Alamein in October 1942 as part of the British North African campaign. Then the military industrial complex kicked into high gear and started making about 1,000 Shermans a month from 11 different manufacturers, including the Detroit Arsenal Tank Plant.
The Sherman was not the best of its kind. In a one-on-one fight with a German tank, like a well-armored Tiger, it would probably come up a little short. Its ammunition storage area was vulnerable to enemy fi re, giving rise to another nickname, Ronson, after the lighter. (There was an advertising tagline of the era that ran: "Lights first time, every time.") The Nazis had another, more grisly name for it: "Tommy Cooker," since the Sherman was often part of the British forces, known as Tommies.
Estimates of how many were built vary between 40,000 and 55,000, but even that lowest figure would mean it outnumbered German tanks by about 14:1. So although a solitary Sherman was not a great place in which to spend World War II, there was safety in numbers and (for once) the guys in charge had worked out some ingenious tactics.
Although the Sherman became the most widely deployed tank of the Allied forces, from Normandy to the Pacific, ubiquity wasn't the only thing in the M4's favor. It was also highly mobile (top speed was 29 mph); reliable (which the German tanks were not); easy to fi x (sometimes unnervingly so- there are stories of field mechanical teams mending a hole made by an enemy shell, cleaning out what remained of the previous crew, and sending the tank back out to battle); and it had an approximate range of 100 miles on a tank of gas or diesel, depending on the engine.
The first batch had Wright R-975-C1 nine-cylinder radial engines, but these were much coveted by the aviation industry, so later models either had twin GMC diesels or a Chrysler A57 Multibank engine with five straight-six heads on a single crank. Chrysler claimed that the engine could still move the tank even if 12 of the 30 cylinders had been knocked out. Total weight was 31.7 tons, although some iterations would approach 40. Early models ran on a vertical volute spring suspension that featured conical springs; later Shermans employed a horizontal-spring version.
Ordnance was a 75mm main gun set in the fully traversable turret (later upgraded to a 76mm; it doesn't sound like much of a difference, but apparently it was a big improvement), two .30 Browning M1919A4 machine guns, and a .50 Browning M2HB machine gun. Some versions had an R3 flamethrower instead of the main gun, which gave rise to another cigarette lighter-inspired nickname: "Zippo." The Sherman was usually operated with a crew of five: a commander, gunner, loader, driver, and a co-driver/hull gunner.
After WWII, the Sherman, which ended up being made in roughly seven variations (including an amphibious version), was sold to other countries' defense forces and therefore took part in various conflagrations around the globe, like the Korean war, the Lebanese civil war, and the Arab-Israeli Six-Day war. It remained in active service until the 1990s. Which is pretty impressive, considering production stopped in 1945.