Explained: this is why traffic lights are green, red and yellow

Have you ever wondered why traffic lights have the colors they do? One day, someone had to pick the colors for traffic lights and they chose green, yellow, and red. Why is that? Perhaps you’ve never really thought about it. Or maybe you’ve been pondering it for many years now. Either way, you’ll get an answer to that question today. Find more information below.

Origin

To understand why these colors were chosen, it’s helpful to know a bit about the origin of traffic lights (and their colors). The first traffic light was installed in the country in 1910. Policemen used whistles and lights to let drivers know when to stop and when to go, to keep the flow of vehicles. In 1920, William Potts created the first traffic light. At that time, there was no regulation about what kind of lights or patterns had to be used. So, these lights looked different everywhere you went. In 1935, the Federal Highway Administration issued the “Manual on Uniform Traffic Control Devices,” setting standards for all signs and signals. This manual also required traffic lights everywhere to be red, yellow, and green.