All corn can’t become popcorn, the kernel’s skin in something like yellow corn is too thick. So after corn was domesticated another variety with thinner skin had to emerge before the first popcorn could be made.

Imagine just trying to roast the staple crop you’ve grown up eating and it suddenly explodes and turns into this feather light white fluffy thing. If I didn’t grow up knowing what popcorn was I don’t know what I’d think.