Traffic lights are signaling devices used to control the flow of traffic at intersections, pedestrian crossings, and other points on the road. They operate using a universal color system: red means stop, yellow (amber) signals that the light is about to change and warns drivers to prepare to stop, and green allows traffic to proceed when safe. By providing clear and timed instructions, traffic lights help prevent collisions, ensure smoother traffic flow, and create safer conditions for both drivers and pedestrians.