In some of the most recent cars in the marketplace, you can change gears by simply pressing a button, turning a knob or toggling a small joystick. Yet at the same time, plenty of different vehicles still require motorists to make use of one foot for the clutch pedal and another for the gas, all when using one hand to control the gear-change lever through a definite design of positions. And several other current cars don’t have any traditional gears at all in their transmissions.
But regardless of whether a vehicle has a fancy automatic, an old-school manual or a modern-day continuously variable transmission (CVT), each unit must do the same job: help transmit the engine’s output to the traveling wheels. It’s a complex task that we’ll try to make a bit simpler today, you start with the basics about why a transmitting is needed to begin with.
Let’s actually begin with the typical internal combustion engine. As the fuel-air blend ignites in the cylinders, the pistons begin moving up and down, and that motion is utilized to spin the car’s Variable Speed Transmission crankshaft. When the driver presses on the gas pedal, there’s more fuel to burn in the cylinders and the whole process moves faster and faster.
What the transmission does is change the ratio between how fast the engine is spinning and how fast the driving wheels are moving. A lower gear means optimum efficiency with the tires moving slower than the engine, while with a higher gear, optimum performance includes the wheels moving quicker.
With a manual transmission, gear shifting is handled by the driver with a gear selector. Many of today’s vehicles possess five or six ahead gears, but you’ll discover older models with from three to six forwards gears offered.
A clutch is used to transmit torque from a car’s engine to its manual transmission. The many gears in a manual transmitting allow the car to visit at different speeds. Bigger gears offer 
plenty of torque but lower speeds, while smaller sized gears deliver much less torque and allow the car travel quicker.