Fibers are the smallest visible units from which yarns are made to produce other materials. Usually, they are knitted or woven into fabrics; however, products such as paper and fiberglass are also made of fibers.
Staple Fibers - Staple fibers are short length fibers, measured in inches, which are spun together to form a yarn. Yarns that are made from staple length fibers are known as staple length yarns.
Filament - Filament fibers are long continuous fibers, ranging in length from 400 to 1,300 yards or more for silk to the relatively unlimited length of some of the man-made fibers. Yarns from filament fibers are known as filament yarns.
Yarn - A yarn is a continuous strand of fibers. It is the basic material which is made into fabric.
In terms of fabrics, most fibers fall under one of two categories: natural or synthetic.
Natural fibers come from plant or animal sources such as cotton, flax, sheep's wool or silkworm cocoons. Manufacturers can spin these materials into threads without having to alter them in any major way.
Synthetic fibers come from man-made processes and chemicals. Fibers such as polyester and nylon are made of chemical polymers spun into threads. However, some synthetic fibers come from natural sources. For example, modal and rayon come from wood cellulose that uses chemical processes to convert wood into fiber.