The selection of types of yarn for knitting is very wide. The weights, or yarn thicknesses, vary from thin enough to produce finely knit baby outfits to chunky types used to create rugs. The materials of yarn for knitting also vary widely. Synthetic as well as natural fiber yarns are available in a large collection of colors. In general, the thinner or more synthetic a knitting yarn is, the lower its price.
Lace, baby and sock yarns are examples of narrow, or fine, knitting yarn. Worsted is the most common type of knitting yarn; it's medium in thickness, or weight. Double knitting, or sport, yarn is thicker than the fine types, but not as thick as worsted weight. The heaviest, thickest types of yarn for knitting are those sold as bulky or chunky for heavy blanket or rug making or as materials for general crafting.
Aran yarn is a specialty type that has a thickness in between that of worsted and chunky. It's not commonly sold in North America, but is readily available in the United Kingdom (UK). This raw wool yarn originated in the Aran Islands near Ireland. It's off-white or cream in color and, as it contains natural oils, it has water-resistant and insulating properties. Aran knitting is always done in the one natural color, yet its many rich pattern stitches result in garments and blankets of many interesting textures.
Other types of natural knitting yarns include angora, cashmere, llama, silk, bamboo, cotton and wool. Wool yarn is a general term for the hair of goats, sheep, llamas or other animals that is spun into long narrow pieces and wound into balls, or skeins. Angora yarn is beautifully silky and is made from rabbit fur. Cashmere is a popular, super-soft wool made from the hair of the Kashmir goat. Silk yarn is spun from the natural thread produced by the silkworm.
Bamboo is a relatively new, natural type of yarn for knitting. It's considered an environmentally friendly option, as it's made from fast-growing and easily renewable bamboo grass. Environmentally safe dyes are often used in the production of bamboo knitting yarn. Cotton yarn, a plant-based material, is a longtime favorite for thinner, absorbent knitting projects such as dish cloths and summer-weight tops. Recently, organic cotton yarn has become popular for knitting; it's made from plants that weren't treated with any commercial pesticide.
Synthetic knitting yarns are made from humanmade fibers. They are usually less expensive than natural yarns for knitting, but not as elegant-looking. Acrylic is the general label that means a yarn is synthetic. Some knitting yarns blend both synthetic and natural fibers to create different benefits such as affordability with softness.