HID (High-Intensity Discharge) headlights are a type of automotive lighting that uses an electric arc to produce bright light. Unlike traditional halogen bulbs, which rely on a filament, HID headlights contain gas and electrodes. When electricity passes through the gas, it creates a high-intensity light that is more efficient and longer-lasting. These headlights are known for their bright, white light, which improves visibility at night and in poor weather conditions. HID headlights are commonly found in luxury vehicles and can be retrofitted into other cars. However, they require a specific ballast to regulate the electrical current for proper operation.