In some of the most recent cars available, you can shift gears by simply pressing a button, turning a knob or toggling a small joystick. Yet simultaneously, plenty of different vehicles still require drivers to make use of one foot for the clutch pedal and another for the gas, all while using one hand to manipulate the gear-change lever through a distinct design of positions. And several other current vehicles don’t possess any traditional gears at all in their transmissions.
But regardless of whether a vehicle includes a fancy automatic, an old-school manual or a modern-day continuously variable tranny (CVT), each unit has to do the same work: 
help transmit the engine’s result to the traveling wheels. It’s a complicated task that we’ll try to make a bit simpler today, you start with the fundamentals about why a transmitting is needed in the first place.
Let’s actually start with the typical internal combustion engine. As the fuel-air blend ignites in the cylinders, the pistons begin moving up and down, and that Variable Speed Drive Motor movement can be used to spin the car’s crankshaft. When the driver presses on the gas pedal, there’s more fuel to burn off 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 lesser gear means optimum performance with the tires moving slower than the engine, while with a higher gear, optimum performance comes with the wheels moving quicker.
With a manual transmission, gear shifting is handled by the driver via a gear selector. A lot of today’s cars possess five or six forwards gears, but you’ll discover older models with from three to six forward gears offered.
A clutch is used to transmit torque from a car’s engine to its manual transmitting. The many gears in a manual transmission allow the car to travel at different speeds. Bigger gears offer lots of torque but lower speeds, while smaller sized gears deliver much less torque and allow the car travel more quickly.
