(I warned you guys it'd be Plant Chat when I ran out of stuff to say.)
Zea mays is the taxonomic name for corn, or maize. "Corn" was used as a generic term for all grains in Europe for many years, until Columbus reached the New World, and they needed a name for that big green stalk with the ears of stuff on them. So it was corn, the generic term, then it got more specific, then Europeans got confused, then the term Maize was used instead, but North American settlers were left going "but... that's corn in that field, isn't it?" and, well, welcome to why taxonomy and "Latin" names exist. I'm gonna call it maize from here on out 'cause it's not as stuffy as using the taxonomic name, but it lessens confusion.
Maize is the human race's earliest, most drastically engineered crop. Yeah, that's right. Genetically engineered. No, it was not Big Ag who engineered it, it was the central Mexican peoples who lived in that area about 9,000 years ago. (Debate rages over the exact time. I'm going with what the genetic evidence says.) Because, you see, maize doesn't exist in the wild.
Maize is an entirely human-dependent crop, and it has been for nine thousand years, ever since the local people took a grass (or five) and bred it into a cold-intolerant, nutrient-sucking, unable-to-germinate-alone food crop that existed for humans, and at the mercy of them.
The original grass, teosinte, is really a group of grasses - five species of the Zea family. Even after extensive genetic testing, no one's sure which grass gave rise to modern maise. (Many botanists and other plant freaks speculate that the genetics are inconclusive because maize is, in fact, a hybrid of two or more of those five teosinte species.) But however it came about, maize was deliberately bred to grow in a tightly-furled stalk, with an inordinate number of leaves wrapped tightly over the seed head (aka the corn cob). Those leaves, which protect the maize beautifully until man comes by to pick it and shuck it, make it impossible for the plant to drop the seeds naturally, meaning it cannot procreate without human help. If left alone, with no humans to interfere, the average corn field would rot into the ground and within three or four years, produce no maize at all. (I've seen it happen, time and again, here in dairy country, when fields are allowed to go fallow.)
The native Americans were pretty smart, and within a couple thousand years, the use of maize had spread to pretty much everywhere it was possible to grow it in the New World. Most of the cultures processed the hard maize with lye (wood ash soaked in water). I suspect it was originally done to soften the grain and make it easier to cook and eat, but chemically, lye also breaks down some of the nutrients and makes them easier for the body to use - most notably, B complex vitamins. Well, it doesn't take a genius (and those native peoples were damn smart, mark my word) to realize those eating the maize processed with lye were healthier, and more and more people did it that way.
Then, of course, the Europeans showed up and wiped out some of the greatest civilizations in the history of the world, and while they were at it, they took maize back to the Old World as a food crop. But the native Americans had the last laugh - the Europeans didn't take along the processing secrets, and Europeans died rather hideously of pellagra, B-vitamin deficiency. This led, rather understandably, to maize being, well, not so popular in Europe, and it rarely (if ever) became a true staple grain crop in the Old World before the advent of modern nutrition and the understanding it brought us.
The native Americans just kept on eating their lye-processed corn (often as tortillas), and to this day it is a major part of many traditional diets.
(Golden maize ears, Moche culture, 300CE.)
With the modern age brought modern genetic engineering (unlike that safer, more traditional stuff), and the advent of high fructose corn syrup and other evils. Proving that, as is often the case, the native peoples had the right idea and we should stick with their methods.
Go eat your tortillas.