Pork is meat derived from hogs. Wild hogs were domesticated during the Stone Age, about 8,000 years ago, and were imported to the New World in the 1500s by early explorers. Since hogs flourish on a diet of corn, most hog farms in the United States are located in the corn belt of the Midwest. Only a third of the pork produced each year is eaten fresh. Most pork is smoked, cured, or processed. Pork is available as chops, roasts, spareribs, ham, bacon, Canadian bacon (low-fat bacon resembling ham), sausage, and a wide variety of luncheon meats, including liverwurst.