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 ...

Is it there for aesthetic value or something more? If you live in the U.S., you're familiar with the holes in the prongs of electrical plugs. Many, if not most, American plugs have them. So what ...

The US uses two standard electrical plug types: Plug Type A and Plug Type B. Both have two parallel pins for power, while the latter has an additional grounding pin for safety. But if you look closely ...