system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do some electronics use all 3 prongs to plug into the wall, but others only use 2 (based on US wall sockets and electronics)?
gpt
The third prong is the ground, which is used as a 'safe exit' for power -- particularly you'll find grounds on higher power devices, particularly those with metal enclosures, as they'll want to be able to ground a short circuit, should a wire inside come loose and make contact with the shell.

This could prevent you from getting a nasty shock from a broken microwave, for example.