system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is it Universally accepted that Green means GO and red means stop?
gpt
I don't know about green being universally accepted as "go", but the fact is that red is accepted as "stop"

The reason for this is simple:
Red light penetrates better (whether it be through fog, smoke, rain, etc), due to its wavelength.

Now say you're driving on a super foggy day, and approach a stoplight. If it's green, but you didn't see it and you drive past the intersection, everything is a-okay. Now if you're suppose to stop, and you drive through the intersection, that's just disaster waiting to happen.

That's why you need a color that can penetrate well to represent "stop". Of course, throughout the years after it was implemented, humans are now programed through habit to relate "red" with ''stop"