CFCs stands for Chlorofluorocarbons,CFCs are halogenated hydrocarbons made up of carbon and halogen (Chlorine and Fluorine) only. These are colorless,odourless,non -flammable and non -toxic chemicals.
These are usually inert or unreactive in lower atmosphere but can react in upper atmosphere thatswhy CFCs are particularly harmful to environment bcoz in the upper atmosphere these chemicals destroy the protective ozone layer and inturn causes global warming.