Red is used exclusively for regulatory road signs prohibiting doing something. So, a stop sign is red because you are ...

Traffic signs have to communicate crucial information quickly and simply, to anyone who might be on the road. They use letters and numbers to lay out information in plain language but they also use ...

Most road signs are easy to understand, as they're pretty literal. Do Not Enter simply means to stay away from that certain area. Speed Limit 55 tells you that you shouldn't go over 55mph. No Passing ...