Yarn

Yarn is a continuous strand of fibers used in knitting, crocheting, weaving, and sewing. It can be natural (wool, cotton, silk, linen) or synthetic (acrylic, nylon, polyester), or a blend. The fiber content, twist, and ply determine texture, strength, elasticity, and warmth.

Production and classification: Yarn is produced by spinning fibers to form a cohesive thread. Singles may be plied to give strength; plying combines two or more singles. Yarns are classified by weight or thickness, such as lace, fingering, sport, DK, worsted, aran, and bulky. They may also be described by fiber type or by twist direction (S-twist or Z-twist). Finishes like mercerization or dyeing may alter appearance.

Applications and history: Yarns are fundamental to textiles, used in clothing, home textiles, and crafts. The technology of yarn production dates to ancient times and evolved through spinning wheels, spinning jennies, and mechanized mills during the industrial era. Modern yarns include natural fibers, synthetics, and blends, with specialized versions for performance fabrics.

Yarn in computing: Yarn is also the name of a package manager for the Node.js JavaScript runtime. Developed by Facebook and subsequently maintained by the open-source community, Yarn manages project dependencies, caches packages for offline installation, and creates a deterministic install through a lockfile (yarn.lock). It supports workspaces to manage monorepos and seeks to provide faster, more reliable installs than npm in some scenarios.