In some of the newest cars on the market, you can change gears by simply Variable Speed Drive Motor pressing a button, turning a knob or toggling a little 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 when using one hand to manipulate the gear-change lever through a distinct design of positions. And many other current vehicles don’t possess any traditional gears at all in 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 has to do the same work: help transmit the engine’s output to the driving wheels. It’s a complex task that we’ll try to make a little simpler today, you start with the fundamentals about why a transmitting is needed in the first place.
Let’s actually begin with the normal internal combustion engine. As the fuel-air blend ignites in the cylinders, the pistons begin upgrading and down, and that 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 complete 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 wheels are moving. A lower gear means optimum performance with the wheels moving slower compared to the engine, while with an increased gear, optimum performance comes with the wheels moving faster.
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 find older models with anywhere from three to six forwards gears offered.
A clutch is used to transmit torque from a car’s engine to its manual tranny. The various gears in a manual tranny allow the car to visit at different speeds. Larger gears offer lots of torque but lower speeds, while smaller gears deliver much less torque and invite the car 
travel more quickly.