CFC, or chlorofluorocarbon, is a type of chemical compound that was commonly used as a refrigerant in air conditioning and refrigeration systems. These compounds are known for their ability to efficiently transfer heat, making them effective in cooling applications. However, CFCs are also harmful to the environment, particularly the ozone layer, as they can break down ozone molecules in the atmosphere. Due to their negative impact on the environment, the use of CFCs has been largely phased out under the Montreal Protocol, an international treaty aimed at protecting the ozone layer. Alternatives, such as hydrofluorocarbons (HFCs) and natural refrigerants, are now being used to reduce environmental harm while still providing effective cooling solutions.