The corn grown that’s not for human consumption is only because it’s earmarked for feed or biofuels. Corn is corn. Where I live, 1 in 4 fields is “for human consumption”

Filed corn is harvested at a different time resulting in a dryer product.

But yes if people get hungry enough, field corn easily qualifies as actual food.

There are 4 types of corn. Dimple/dent corn, pop corn, sweet corn, and flint corn. Each variety can be eaten. Prepared differently of course as they have different starches and flavors but the vast majority of corn fields in the United States grow dent corn for feed and biofuels.

Fair point, there’s many types of corn but for anyone interested.

Sweet Corn: For Fresh Eating and therefore harvested with a high moisture content which hurts preservation without freezing and total yield.

Dimple is a Field corn, harvested later resulting in a dryer product, lasts longer and has a higher yield.

Flint Corn: Mostly decorative as it looks cool, but again still edible after grinding.

Heirloom: lots of shapes and sizes but significantly lower yield.

Popcorn: A tiny slice of the market but pops when heated.

Heirloom is just corn passed down from your pop-pop ;) (though the category now stands for rare varieties of corn that came from family farms or from the years long since passed).

Corn is amazing. My favorite use of it is for alcohol though.

Aren't there different varieties of corn?

Yes, and they are all edible. But not all are palatable.

Yeah, we're pretty good at making pretty damn anything "fit for human consumption", including quite a few things that are outright poisonous if consumed unprocessed.

Related: https://en.wikipedia.org/wiki/Nixtamalization

(Corn doesn't need special processing to be edible, but it does need special processing if you want to avoid dying from nutritional deficiency when having a corn-based diet).