Fibres are units of matter having length at least 100 times their diameter or width. The term “textile fiber” means a unit of matter which is capable of being spun into a yarn or made into a fabric by bonding or by interlacing in a variety of methods including weaving, knitting, braiding, felting, twisting, or webbing, and which is the basic structural element of textile products.

Fibres suitable for textile use possess adequate length, fineness, strength, and flexibility for yarn formation and fabric construction. Other properties affecting textile fibre performance include elasticity, crimp (waviness), moisture absorption, reaction to heat and sunlight, reaction to the various chemicals applied during processing and in the dry cleaning or laundering of the completed fabric, and resistance to insects and microorganisms.

A fiber can be classified into Natural Fibers and Man made fibers. Natural fibers can be further classified into Animal Fibers, Vegetable fibers and Mineral Fibers.

Man Made fibers can be further classified into Natural Polymer Fibers, Synthetic Polymer Fibers and In-Organic or Refractory fibers. (The chart elaborately describes the classification of fibers. A filament is a fiber of relatively very long length. Silk is the only natural filament.