<s>[INST] What is denim made of, and how did it come about? [/INST] Denim is almost always made from cotton, and is formed by weaving two yarns together. Usually, one of the two yarns is dyed, giving the denim garment its color.

While denim was popularized in the western United States in the 19th century, it was actually first produced in Nimes, France, in the late 17th century. Weavers accidentally created it while trying to replicate another popular fabric known as serge. The new fabric was called "serge de Nimes" which eventually was shortened to denim.</s>