1. Monofilament: a single filament
2. Multifilament: A tow composed of multiple filaments, which is further divided into untwisted multifilament and twisted multifilament.
3. Composite twisted yarn: Twisted multifilament yarns are combined and twisted one or more times.
4. Textured yarn: elastic or highly bulky yarn made of synthetic fibers that plasticize and deform when heated. For example: network yarn, elastic yarn
