In mechanics, a transmission (also called a "standard" or "manual" transmission) or gearbox, is the system of gears and/or the hydraulic system (called variously "hydrodynamic", "fluid" or "automatic" transmission) that transmits mechanical power from a prime mover—such as an engine or electric motor—to some form of useful output device, normally rotary in form, and generally at a reduced rate of angular speed but at a higher motive torque.
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