Across the United States, drivers are looking up at intersections and noticing a new, unfamiliar glow: small blue lights perched near traditional red, yellow and green signals. They are not decorative ...

Those blue lights above traffic signals aren’t decorative. Here’s what they’re for and why more cities are installing them. Blue confirmation lights help police spot and enforce red-light violations ...

Some things are so ubiquitous that it's easy to forget they're designed for a reason. With more than 300,000 traffic lights set up across the United States, it's easy to take how they look for granted ...