The car quartet is a group of four components that are essential for a car to function properly. The first component is 'WHEELS', which are the round objects that are attached to the axles and provide the car with its mobility. The second component is 'TIRES', which are the rubber coverings that are placed around the WHEELS and provide traction and cushioning. The third component is 'turbo', which is an engine modification that increases the power output of the engine. Together, these four components make up the car quartet and are essential for a car to run smoothly.