This video explains how to crochet the chain stitch. A chain is the foundation of every crochet project. In other words, all crochet projects begin with a chain. The chain is made of many chain stitches. The number of chain stitches in the chain is determined by the pattern you are using. The chain may be as short as 2, or as long as 200. It just depends on the pattern. In crochet patterns, chain is abbreviated as ch. This is how you crochet a chain stitch.