Using the principle of mechanical advantage, transmissions provide a torque-speed conversion (commonly known as "gear reduction" or "speed reduction") from a higher speed motor to a slower but more forceful output. Explanation Early transmissions included the right-angle drives and other gearing in windmills, horse-powered devices, and steam engines, in support of pumping, milling, and hoisting. Most modern gearboxes either reduce an unsuitable high speed and low torque of the prime mover outp… (More on Gearbox)