What is the purpose of car fog lights?

[DelMadison]

Car fog lights are used for road illumination during rainy or foggy weather conditions. They can penetrate thick fog and serve to alert oncoming drivers, making it easier for drivers behind to spot your vehicle. They are primarily used in environments with low visibility such as fog, snow, rain, or dust. Fog lights can increase the operational distance. In foggy conditions where visibility is low and the driver's line of sight is restricted, the strong light penetration of yellow anti-fog lights can enhance visibility for both the driver and other traffic participants, allowing approaching vehicles and pedestrians to detect each other from a greater distance. Fog lights should only be turned on when visibility is below 200 meters.