Despite its ubiquity, the automatic transmission is one of the most mechanically complex parts of the modern automobile. Transmissions allow your gas-powered car to operate efficiently over a wide range of speeds. Ever notice how you can both cruise on the highway at 80 mph and putt around town at 30 without your engine screaming its head off during the former?
A transmission with multiple gears is what makes that possible. The enthusiast-favorite manual transmission supplies you with a clutch pedal and a gear selector that lets the driver do this, well, manually, but the vast majority of cars today are equipped with automatic transmissions.
