Perfluorocarbons or PFCs, are organofluorine compounds with the formula CF, meaning they contain only carbon and fluorine. The terminology is not strictly followed and many fluorine-containing organic compounds are  also called fluorocarbons. Compounds with the prefix perfluoro- are hydrocarbons, including those with heteroatoms, wherein all C-H bonds have been replaced by C-F bonds. Fluorocarbons includes perfluoroalkanes, fluoroalkenes, fluoroalkynes, and perfluoroaromatic compounds.