A cigarette is a narrow cylinder containing psychoactive material, usually tobacco, that is rolled into thin paper for smoking. Most cigarettes contain a "reconstituted tobacco" product known as "sheet", which consists of "recycled [tobacco] stems, stalks, scraps, collected dust, and floor sweepings", to which are added glue, chemicals and fillers; the product is then sprayed with nicotine that was extracted from the tobacco scraps, and shaped into curls.