In some of the newest cars on the market, you can shift gears by simply pressing a button, turning a knob or toggling a little joystick. Yet at the same time, plenty of different vehicles still require drivers to use 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 cars don’t have any traditional gears at all within their transmissions.
But whether or not a vehicle has a fancy automatic, an old-college manual or a modern-day constantly variable transmission (CVT), each unit must do the same work: help transmit the engine’s output to the generating 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 combination ignites in the cylinders, the pistons start upgrading and down, and that movement is utilized 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 quicker and faster.
What the transmission does is change the ratio between how fast the engine is spinning and how fast the driving Variable Speed Transmission wheels are moving. A lesser gear means optimum efficiency with the tires moving slower compared to the engine, while with an increased gear, optimum performance comes with the wheels moving quicker.
With a manual transmission, gear shifting is handled by the driver via a gear selector. Many of today’s cars possess five or six ahead gears, but you’ll discover older models with 
from three to six forwards gears offered.
A clutch can be 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 plenty of torque but lower speeds, while smaller gears deliver less torque and allow the car travel more quickly.