What does automatic headlight on/off mean?

[AbigailDella]

Car manufacturers have installed a photosensitive control system for the headlights to facilitate users, which can automatically turn on and off according to the brightness of the light. This is called "automatic headlights". Most high-end vehicles are equipped with this feature. Introduction to automatic headlight on/off: For cars equipped with automatic headlights, when the light becomes dim during driving, the headlights will automatically turn on, and when the light becomes bright, they will automatically turn off. Principle of automatic headlights: Electronic components such as photoresistors are used as sensors and installed behind the rearview mirror inside the car. They send electronic signals to the ECU (electronic control unit), similar to a computer CPU, to inform the ECU whether to turn on or off the headlights, or to switch between high and low beams. The ECU controls the headlight switch and beam changes. When driving, if the light suddenly becomes dim, the headlights will automatically turn on, and when the light is sufficient, they will automatically turn off. Additionally, during nighttime encounters with other vehicles, the headlights may automatically switch between high and low beams.