In terms of lights, what do signal lights indicate?

Signal lights are essential components of vehicle communication and are specifically designed to indicate the driver's intended direction of travel. When a driver uses their turn signal, they are informing other road users of their intention to turn left or right, or to change lanes. This communication helps to enhance safety on the road by allowing other drivers, pedestrians, and cyclists to anticipate the vehicle's movement, thereby reducing the potential for accidents.

The other options do not accurately reflect the primary function of signal lights. For instance, vehicle speed and distance are typically displayed through the speedometer and odometer, while braking intensity is usually indicated by brake lights. Headlight brightness and angle are also separate functions that pertain to visibility rather than directional intent. Thus, signal lights uniquely serve the crucial purpose of communicating directional changes.