- A key component to the functionality of a manual transmission is the use of a driver's foot to engage or disengage the clutch mechanism. The clutch mechanism, which is operated automatically in an automatic transmission, requires manual (physical) operation on the part of a driver. The clutch is what allows the transmission to be shifted into various gears, and it is what allows the transmission to be engaged or disengaged.
- Along with the manual operation of a car's clutch mechanism, another key component to the operation of a manual transmission is the use of a driver's arm to manually shift the manual transmission gear. Unlike an automatic transmission, which uses fluid under pressure to shift the transmission gears, a manual transmission requires strength on the part of a driver to shift the transmission into the appropriate gear.
- A manual transmission requires the ability of the driver to know when to engage the clutch mechanim, as well as when (at what speeds) to shift in and out of the various gears. Unlike an automatic transmission, which has preset shift points, a manual transmission enables a certain amount of leeway when it comes to shifting the transmission gears. A driver can either go by the sound of the engine--the engine will normally "whine" or "whirly" when it's time to shift--or a driver can use the tachometer, or rpm gauge, on the car's dashboard to know when to engage the clutch and shift into the next gear.
