Acid rain is formed when sulfur and nitrogen dioxides from fossil fuel combustion mix with atmospheric moisture such as rain, fog, or snow to produce acidic components that are deposited through wet or dry means. Wet deposition includes acidic rain, fog, and snow that affect plants and animals upon falling to the ground, while dry deposition incorporates the acidic chemicals into dust or smoke that falls to the ground through other means. The document aims to explain what acid rain is, how it is formed, its effects on the environment and human populations, and ways to reduce acid rain deposition.