Tripe is the name for the stomach tissue of domesticated animals, such as cows, sheep, pigs, etc., when eaten as food. It often contains remnants of the butchered animal's last meal, and therefore must be cleaned meticulously prior to human consumption.
Tripe is consumed in many parts of the world, most commonly as an ingredient in sausages, soups, and stews. Many Americans are unaware when they are being fed tripe. Some types of hot dogs, for example, are made with it.