If you've ever wondered how traffic lights work and how they can detect your car, you've probably also been curious about those small blue lights mounted above the signals themselves. These blue ...

Red and green traffic lights have been around since the 1800s, when British traffic officers used to rotate gas lamps that burned red and green to control the movement of mostly horse-drawn vehicles.

(WHTM/NEXSTAR) – On many traffic signals found throughout the United States, there is a small light that is placed in between or off to the side of the traffic signal lights. Sometimes you see them ...

PENNSYLVANIA (WHTM) — On many traffic signals found throughout the United States and Pennsylvania, there is a small light that is placed in between or off to the side of the traffic signal lights.