Ozone is a molecule of oxygen with 3 atoms i.e., O3. It is formed due to sunlight at higher levels with higher wavelength.

Ozone is found in stratosphere shielding the earth by protecting it and by not allowing UV rays to reach the earth.
If these rays will reach the earth then many harmful diseases are caused like skin cancer, cataract, it also affects the growth of plants and vegetation. Two steps to limit the damage of this layer are:
(i) Do not use aerosols, or any products which will release CFC (chlorofluorocarbon) in the atmosphere.
(ii) Ban on use of CFC as refrigerant and in fire extinguishers.