When headlights must be activated during times of darkness and when visibility is limited?

Headlights must be activated during times of darkness, such as after sunset and before sunrise. Additionally, they should be used when visibility is limited due to weather conditions like rain, fog, or snow, where distance and clarity are compromised. It's important to ensure that your headlights are functioning properly to enhance safety for yourself and other drivers. Always follow local laws regarding headlight use.