Taillights are red lights located at the rear of a vehicle, designed to signal the presence and actions of the vehicle to others on the road. They illuminate when the vehicle's headlights are turned on and become brighter when the brakes are applied, alerting drivers behind to the vehicle's slowing or stopping. In addition to their primary function, taillights often include turn signal indicators that flash to indicate a change in direction. Modern vehicles may also feature LED taillights, which are more energy-efficient and have a longer lifespan compared to traditional incandescent bulbs.