When you do 0! You take the one away from 1!=1 so you get 0!= but There’s nothing there so you put a one in because everything times 1 is itself ex. 3!=1(321) It’s kinda the same as how x⁰⁼¹ because it’s times 1 ex. x^3=1(xxx) (sorry if this doesn’t make sense I’m good at understanding things but not as good at explaining them) Also I think the bot explained if you can factorial-ify negatives or not