Alcohol is produced when yeast in the absence of oxygen ferment a food source like grains or grapes. The sugar in these food sources is converted to alcohol. Humankind has been drinking beverages that contain alcohol for thousands of years. In fact, the ancient Egyptians paid their slaves with beer. Along with low alcohol content, these ancient beers were a good source of vitamins and antibiotics like tetracycline, the reason some mummies glow under ultraviolet lights. Today, alcohol-containing beverages do not have a plethora of vitamins and tetracycline because society has focused on maximizing the alcohol content.
Alcohol is both a beverage providing some sustenance and a drug. For thousands of years, alcohol has been consumed in a medicinal, celebratory, and ritualistic manner. It is drunk in just about every country and often in excessive amounts. Alcohol can be made from a variety of different starch foods through the processes called fermentation. Fermentation of starchy food such as barley or wheat can produce ethanol and CO2which makes up what is commonly known as beer.