The job of the car's transmission system is to transmit the power made in the engine to the wheels of the car and consists of the clutch, gearbox, drive shaft, universal joints, rear axle and wheel. The manual transmission gearbox comes into play by enabling the driver to select the right gear for the speed the car is travelling at, ensuring the engine can function as efficiently as possible.

The manual transmission gearbox is normally attached by bolts to the back of the engine, next to the clutch.

In a manual transmission gearbox, the driver controls the gears manually by releasing the accelerator pedal whilst pressing the clutch foot pedal and engaging the correct gear for the driving conditions and speed. Then the clutch is released and pressure reapplied on the accelerator. The correct gear is selected by hand, using a gear stick, which operates the gear linkage (a series of levers and rods) enabling the correct gear to be engaged. A driver of a car with a manual gearbox can normally select from between four to six forward gears, one reverse gear and neutral position.

The manual transmission gearbox tends to be more fuel efficient than automatic or continuously variable gearbox transmissions. The gearbox manual transmission, although built to last and easy to maintain with proper care and attention, will wear out and need replacing. Careless driving, such as choosing the wrong gear by mistake, can speed up wear and tear and cause damage to the manual transmission gearbox.