Blue stop signs really exist! Here's where you'll find them, what they mean and what to do if you see one on the road.

So if you’ve ever spotted a pink traffic sign, you’re probably wondering when the heck that came into play. Unlike the elusive blue stop sign, pink traffic signs are more common than you think.

But while it’s rare, you might come across a blue stop sign, either on a United States roadway or abroad. What does a blue stop sign mean, and where might you see one? Are they used for purposes ...