There are dozens of types of yarn, but yarn fiber can be broken down into two basic categories: natural and synthetic. Natural year fiber includes yarn that is made from cotton, wool, silk, and alpaca fibers. There are also yarns that are made from silk and bamboo yarn fibers. There are even natural yarns made from llama hair and dog hair.
On the other hand, there are yarns made from synthetic materials such as rayon, nylon, and acrylic. Yarns made with natural fibers are usually more expensive than yarns made with synthetic fibers. This is especially true if the fibers are produced in an organic fashion.
Of the categories listed above, there are still many variations within the kinds of yarn. One of the key variations is the way in which the yarn is colored. In some cases, yarn is given no color at all and is used in its natural state. In other cases, fiber is tinted with one of a number of kinds of dyes. Some people who prefer to use all-natural products will chose yarn that is made of yarn that has been dyed with natural vegetable dyes. Other people are fine with using yarn fiber that has been colored with synthetic or chemical dyes.
Another way to color yarn is to hand-paint or hand-dip it. These kinds of yarns are specialty yarns that are tinted to create a very specific effect. The effects usually create variations in the color of the yarn or simply different tones within a single color. These sorts of specialty yarns are usually much more expensive than yarns that are mechanically dyed.
Some yarn fiber is hand spun into yarn while other fiber is spun using machines. Hand-spun yarn, like hand-dyed or painted yarn, is more expensive than the kind that is spun using machines. This is simply because it takes far more human working hours to do these sorts of things by hand than it does to have a machine do the work.
While most yarn fiber comes from plants and animals, there are some speciality kinds of yarn fiber that are actually made with metal. In some cases, silver is used to create a fiber. When silver is used, it is often woven in small amounts into fiber that comes from plants or animals. It can give a wonderful shimmer to a garment and is sometimes even used in fine knitwear.