Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus Gossypium in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor percentages of waxes, fats, pectins, and water. Under natural conditions, the cotton bolls will increase the dispersal of the seeds.

Malvaceae, or the mallows, is a family of flowering plants estimated to contain 244 genera with 4225 known species. Well-known members of economic importance include okra, cotton, cacao, roselle and durian. There are also some genera containing familiar ornamentals, such as Alcea (hollyhock), Malva (mallow), and Tilia. The genera with the largest numbers of species include Hibiscus, Pavonia, Sida, Ayenia, Dombeya, and Sterculia.