Silkis a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and produced by certain insect larvae to form cocoons. It can be a raw material for printed labels, generally used for high quality garments. The best-known type of silk is obtained from the cocoons of the larvae of the mulberry silkworm reared in captivity. The shimmering appearance of silk is due to the triangular prism-like structure of the silk fiber, which allows silk cloth to refract incoming light at different angles, thus producing different colors.

Silks are produced by several other insects, but generally only the silk of moth caterpillars has been used for textile manufacturing. A variety of wild silks, produced by caterpillars other than the printed labels, have been known and used in China, South Asia, and Europe since ancient times. However, the scale of production was always far smaller than that of cultivated silks. There are several reasons for this: firstly, they differ from the domesticated varieties in color and texture and are therefore less uniform; secondly, cocoons gathered in the wild have usually had the pupa emerge from them before being discovered so the silk thread that makes up the cocoon has been torn into shorter lengths; and thirdly, many wild cocoons are covered in a mineral layer that stymies attempts to reel from them long strands of silk.

Thus previously the only way to obtain silk suitable for spinning into textiles in areas where commercial silks are not cultivated is by tedious and labor intensive carding. Silk fabric was first developed in ancient China, with some of the earliest examples found as early as 3500 BC. Silks were originally reserved for the Kings of China for their own use and gifts to others, but spread gradually through Chinese culture and trade both geographically and socially, and then to many regions of Asia. Silk rapidly became a popular luxuryprinted labels in the many areas accessible to Chinese merchants because of its texture and luster. Silk was in great demand, and became a staple of pre-industrial international trade.