In a few of the newest cars on the market, you can change gears by simply pressing a button, turning a knob or toggling a small joystick. Yet simultaneously, plenty of different vehicles still require motorists to use one foot for the clutch pedal and another for the gas, all while using one hand to manipulate the gear-shift lever through a definite pattern of positions. And several other current cars 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 constantly variable tranny (CVT), each unit must do the same work: help Variable Speed Transmission transmit the engine’s result to the driving wheels. It’s a complex task that we’ll try to make a bit simpler today, you start with the fundamentals about why a transmitting is needed to begin with.
Let’s actually start with the typical internal combustion engine. As the fuel-air combination ignites in the cylinders, the pistons start moving up and down, and that motion 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 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 lesser gear means optimum functionality with the tires moving slower than 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. Many of today’s vehicles have five or six forwards gears, but you’ll find older models with anywhere from three to six forward gears offered.
A clutch can be used to transmit torque from a car’s engine to its manual transmitting. The various gears in a manual tranny allow the car to travel at different speeds. Larger gears offer plenty of torque but lower speeds, while smaller sized gears deliver less torque and invite the car travel quicker.