system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why did plugs used to have 1 big prong and one small one, and why don't they have the anymore?

I was just looking at my phone charger and noticed both prongs were the same size (I'm not talking about the ground) and so I started looking at all my other plugs and noticed all prongs are the same size except for really old appliances, why is that?
gpt
If your appliance has a switch, you want it  to interrupt the hot so that all the internal wiring isn't energized (i.e. There is no potential for faults). Different sized blades on the attachment plug dictate which one is hot.