There are a few reasons why the colors red, yellow, and green were chosen for traffic lights. Red is an obvious choice. The color red means danger or to be alert for something occurring.

Talking Transportation Why traffic signals are red, yellow, green — and expensive The first traffic signals were not always the colors you see now. Here’s some history.

Researchers are exploring ways to use features in modern cars, such as GPS, to make traffic safer and more efficient. Eventually, the upgrades could do away entirely with the red, yellow and green … ...

Smarter vehicles could mean some of the most dramatic changes for the traditional traffic signal since the yellow light was added more than a century ago By JEFF McMURRAY The Associated Press ...

Eventually, the upgrades could do away entirely with the red, yellow and green lights of today, ceding control to driverless cars.

Eventually, the upgrades could do away entirely with the red, yellow and green lights of today, ceding control to driverless cars.