Why do some cords have three metal pieces instead of two? And why is the third round instead of the two parallel lines?

Question

Why do some cords have three metal pieces instead of two? And why is the third round instead of the two parallel lines?

In: 0

Answer 1

It’s a grounding wire plug.

A grounding wire is a safety measure to prevent a house fire or an electric shock if there is excess electricity in the wiring system. Ground wires run parallel to other wires in order to safely discharge excess electricity into the ground.

https://us-electric.com/what-is-a-ground-wire/