A circular knitting machine—also known as a circular weft-knitting machine (or more concisely, a circular knitting machine)—features numerous knitting systems (commonly referred to as "feeds"). For example, in a single-jersey latch-needle circular knitting machine, each knitting system consists of latch needles, sinkers, cam carriers, yarn guides, and other components. Each feed constitutes an independent unit capable of forming loops. Due to its high number of feeds and high rotational speed, this machine achieves high production output. Combined with excellent fabric quality, it offers strong product versatility, rapid pattern changes, and fewer processing steps—factors that have driven its rapid development.

Fabrics must be woven, and they are used in clothing, shoes, hats, curtains, bed sheets, car interiors, and more. Modern high-tech fabrics continue to emerge, combining powerful functionality with durability. However, the most common and popular fabrics still share similar structures, varying only slightly.