Chloroform, or trichloromethane, is an organic compound with formula CHCl₃. It is a colorless, strong-smelling, dense liquid that is produced on a large scale as a precursor to PTFE. Chloroform is a man-made by-product formed when chlorine is used to disinfect water. Chloroform is also used in industrial processes. It is a colorless liquid with a pleasant, non-irritating smell and a slightly sweet taste.