Leather is a strong, flexible and durable material obtained from the tanning, or chemical treatment, of animal skins and hides to prevent decay. The most common leathers come from cattle, sheep, goats, equine animals, buffalo, pigs and hogs, and aquatic animals such as seals and alligators.

Cattle are large, domesticated, bovid ungulates widely kept as livestock. They are prominent modern members of the subfamily Bovinae and the most widespread species of the genus Bos. Mature female cattle are called cows and mature male cattle are bulls. Young female cattle are called heifers, young male cattle are oxen or bullocks, and castrated male cattle are known as steers.