The Ozone layer is made mainly of nitrogen and oxygen. It protects Earth from the suns harmful radiation and keeps the planet warm enough for life to exist.
The ozone layer is a part of the Atmosphere. It contains ozone and protects Earth by absorbing most of the suns harmful radiation. Over the last few decades, this natural shield has been damaged by CFCs allowing more of the suns energy to reach the Earth. This contributes to global warming.
CFCs are compounds that contain carbon, chlorine and fluorine. They were used in fridges and spray cans. CFCs are carried by the wind into the atmosphere where they eventually break down and release chlorine atoms that destroy the ozone layer. A hole has formed on the ozone layer and some parts have become very thin. Many countries have cut down on the use of CFCs in an effort to allow the ozone layer to repair itself.