This lecture explains the greenhouse effect, a natural process that keeps Earth warm enough for life, and how human activities are making it stronger, leading to global warming. Students learn how sunlight and heat interact with gases like CO₂, CH₄, and N₂O, why these gases trap heat, and how their sources (factories, vehicles, farming, deforestation) contribute to rising global temperatures. Real-life examples (like a hot parked car) help make the concept easy to understand. The lesson also covers the harmful effects of global warming, including melting ice, rising sea levels, extreme weather, and threats to wildlife. Finally, students explore simple actions they can take to help reduce greenhouse gases.