Ozone molecules are made up of three oxygen atoms, represented by the chemical formula O3. They are found in the Earth's atmosphere, primarily in the stratosphere, where they form the ozone layer. This layer plays a crucial role in protecting life on Earth by absorbing harmful ultraviolet (UV) radiation from the sun. While ozone is beneficial in the upper atmosphere, it can be harmful at ground level. In urban areas, ozone can form as a result of pollution from vehicles and industrial activities. This ground-level ozone can lead to respiratory problems and other health issues, making it important to monitor air quality.