Let’s explore the inner workings of traffic signals. The traffic lights and crosswalk signals at an intersection are only the public user interface, of course. The interesting stuff is going on ...

Question: I’m wondering about a light that seems to only be on at night on the traffic lights. It’s a small purple or blueish ...

Question: I’m wondering about a light that seems to only be on at night on the traffic lights. It’s a small purple or blueish light that’s near the traffic lights.