Have you ever looked at an electrical plug and wondered what those holes in the prongs are? Hunker has all the answers to ...

If you've ever looked closely at an electrical plug, you've likely noticed that the ends of the prongs have little holes in them. While this is a leftover design element from early electrical systems, ...

You find yourself in an airport or hotel room in another country, and you really need to charge your phone, camera or game system. But what is that strange-looking outlet? It has round holes! And ...