Knitting yarn consists of long continuous lengths of interlocking fibers, which are used with two needles to construct fabric. While the origins of spinning fiber to create yarn reach back farther than 20,000 years, yarn that was specifically designed for knitting did not appear until much later, when people learned how to knit. Knitted items have been found in Egypt that date back to the 11th century B.C.
During the 1500s, knitting wool, yarn spun from the fleece of sheep, was widely used for knitting yarn. The aristocracy had garments knitted with silk knitting yarn as well. Elizabeth I is said to have had a preference for silk stockings. The 1500s also saw the invention of the first knitting machines.
Today, three types of fibers are used as knitting yarn: plant fibers, animal-based fibers and synthetics. American cotton is the most popular plant-based fiber, notable for its wide variety of colors. Egyptian cotton is valued for being smooth and soft. Linen, crafted from the flax plant, is valued for its strength. Plant-based yarns are the easiest natural yarns for beginners.
Knitting yarn crafted from animal-based fibers includes wool, mohair, cashmere, silk, angora and alpaca. Animal-based knitting yarn tends to be softer and warmer than other yarn, but can also be more delicate. An exception is silk, which is exceptionally strong. Animal-based yarns are a good choice for hats, scarves and shawls.
Synthetic yarn includes acrylic, nylon and rayon. Synthetic yarn is popular for its ease of care, being both strong and machine-washable. Processed using wood pulp that is attached to thread, Rayon is the more natural looking of the three, with an attractive sheen. With their even ply, man-made yarns are a good choice for beginner knitters.