u/AtmosphereTimely6071

If I put two fingers into the wall socket, I will be cooked (or roasted), therefore clearly the socket does in fact not know that my body should not receive the full amount of power. Or maybe it is my body that does not know?

My question is: How does an electric appliance, like for instance a lightbulb know only to pull like 10 watts from the socket? Or how does the socket know only to supply that little, and not the full flow available? I understand that energy saving bulbs must pull less energy right?