This lecture discusses the environmental concerns related to air pollution, focusing on the invisible killer that can lead to deadly health issues such as lung cancer, stroke, heart disease, and lung disease. It also covers the efforts of organizations like the World Health Organization and the Climate & Clean Air Coalition to reduce short-lived climate pollutants, which are responsible for millions of premature deaths annually. The presentation delves into the impact of pollutants like particulate matter, ozone, nitrogen dioxide, and sulfur dioxide on public health, emphasizing the importance of clean air for a healthy future.