What is the meaning of "rear" in car functions?

On a car, the symbol "rear" represents the function of defrosting and dehumidifying the rear window. When a driver notices fog on the rear window during driving, he or she can press the "rear" button to remove the fog and ensure a clear view for safe driving. Many cars on the market today use an icon to represent this function.

On the rear window, there is a copper wire that acts as a heating element to defrost and dehumidify the glass. When the "rear" button is pressed, this function is activated. Generally, the rear window defrosting function will turn off automatically after about ten minutes to protect the resistance wire from overheating and burning.