Wool is the fiber erived from the fur of animals of the Caprinae family, principally sheep, but the hair of certain species of other mammals such as goats, llamas and rabbits may also be called wool. Wool has two qualities that distinguish it from hair or fur: it has scales which overlap like shingles on a roof and it is crimped; in some fleeces the wool fibers have more than 20 bends per inch.