Beer predates wine as one of the oldest known alcoholic beverages (only mead surpasses it in age), and the discovery of the fermentation of grain is closely linked to the transition from a nomadic society to a settled agricultural society during the Neolithic Revolution.
The fermentation of starchy carbohydrates is a more complicated matter, however, than the transformation of grape sugars into alcohol, as a grain’s starch must be converted into sugar before fermentation can begin. Thus, the aim of the brewing process is twofold: the brewer must first derive the wort, a sugar-rich liquid, from malted grain and then the brewer must ferment the wort. Typically, the raw ingredients required for this process are water, yeast, hops, and a starch source. Hops, the dried flower clusters that provide flavor and bitterness to beer, have both preservative and antiseptic qualities that inhibit bacterial growth. This simple formula was detailed as early as 1516, in the Bavarian Purity Law (Reinheitsgebot), which codified the three ingredients authorized for beer production as barley, hops, and water. The action of yeast in fermentation was at the time undiscovered, and wheat, a component of Hefe-Weizen and white beer styles, was reserved for the production of bread.
In the modern brewing process, the first step is to create the malted barley, or malt. Barley—the cereal grain of choice for most beers—is steeped in water for approximately two days to promote germination of the grain. Once the grain begins to germinate, or sprout, it is transferred to compartments with controlled temperature and moisture levels. As the sprout grows to nearly an inch in length, the enzyme amylase is produced. Amylase converts the starchy carbohydrates of the grain into the fermentable sugars
Since this guide was written some time ago, it's kind of understandable that this still appears: "Tito’s Handmade vodka is an artisan American spirit made in Texas on a much smaller scale, in a pot still, from 100% corn". In 2025 it is projected to pass Smirnoff as the #1 largest vodka brand by volume in the world. They've been sued (and I understand settled quietly) over the words "artisan" and "handmade" and whether it's actually made in pot stills anymore is not particularly clear. I think artisan is clearly no longer true, it's definitely not a smaller scale, and I expect pot still is unlikely, although the cheapness of industrial corn-based alcohol from Missouri makes the claim of corn plausible.