(1) Natural fibers: cotton, wool, hemp, silk. (2) Conventional fibers: viscose fibers, polyester fibers, acetate fibers, polypropylene fibers, polyamide fibers. (3) differentiated fibers: ultra-fine fibers, shaped fibers, low melting point fibers, high curl fibers, antistatic fibers. (4) high functional fibers: aromatic polyamide fibers, carbon fibers, metal fibers.