If you've ever stared at the holes in an electrical plug and wondered why they exist, you're not alone. Like an industrial-age kōan, the answer is anything but straightforward. A quick search will ...

Have you ever wondered what the holes in electrical prongs are for? Well, some knowledgeable experts have the answer. Type A and Type B electrical plugs are the two standard varieties used in the US.

Not all outlet holes are the same, and there's a reason for that. The shapes (vertical slots, round holes, T-slots, etc.) correspond to specific electrical functions and safety features. Take the ...