The wool is a natural fiber that is obtained from the caprine (goat and, mainly, sheep), and of other animals like llamas, alpacas, guanacos, vicuñas or rabbits, using a process denominated shearing. It is used in the textile industry to make products such as bags, blankets, gloves, socks, sweaters, etc. Wool products are mostly used in cold areas because their use maintains body heat; this is due to the nature of the material’s fiber. A large number of sheep breeds and the variable influence of the animal's living conditions act on the characteristics of the wool. The classification of wool is made taking into account some characteristics, of which the most important are: fineness, length, regularity in the degree of curling and uniformity, strength and elongation, elasticity, flexibility, color, brightness, and performance. The world production of washed wool is about 2 million tons, with Australia, Argentina, Chile, China, the United Kingdom, the Soviet Union, New Zealand, South Africa and Uruguay being the main producers.