2. Fiber evidence provides information about where a person has been. Its origin must be narrowed down to one or two sources to be useful in crime scene investigation. (This can be difficult because many clothes, upholstery, and carpets are mass produced.) Fibers are divided into two groups: natural and man-made.

3. Wool Silk Cotton Flax Since the stone age, people have used these materials to make threads that could be woven into large pieces of cloth. During the industrial revolution, this process was mechanized to produce mass amounts of fabric.

4. Rayon (first man-made fiber) Today, synthetic fiber is used twice as much as natural fiber in making fabric. Man-made fibers are generally classified into two groups depending on whether or not they originated from cellulose. Fibers derived from cellulose include rayon and acetate. Fibers not derived from cellulose include nylon, polyester, acrylic, and spandex.