Emission refers to the release of substances, often gases or particles, into the atmosphere. This can occur from various sources, including vehicles, factories, and natural events like wildfires. Emissions can contribute to air pollution and climate change, affecting both human health and the environment. Common types of emissions include carbon dioxide, methane, and nitrogen oxides. These substances can come from burning fossil fuels, agricultural practices, and industrial processes. Monitoring and reducing emissions is essential for improving air quality and mitigating the impacts of global warming.