Knitting is a craft by which thread or yarn may be turned into cloth. Similar to crochet, knitting consists of loops called stitches pulled through each other. Knitting differs from crochet in that multiple stitches are active, or in use, at the same time, and crochet uses a single tool, a crochet hook, instead of a minimum of two knitting needles. The active stitches are held on a needle until another loop can be passed through them with a second needle.
One of the earliest known examples of knitting was finely decorated cotton socks found in Egypt in the end of the first millennium AD. The first knitting trade guild was started in Paris in 1527. With the invention of the knitting machine, however, knitting "by hand" became a useful but non-essential craft. Similar to quilting, spinning, and needlepoint, knitting became a social activity.
Different yarns and knitting needles may be used to achieve different end products, by giving the final piece different colour, texture, weight or integrity. This has led contemporary knitters to create web sites and blogs about their own patterns, techniques, and to showcase their work.