The primary gas released by burning fossil fuels is carbon dioxide (CO2). Fossil fuels, such as coal, oil, and natural gas, are hydrocarbon-based energy sources that, when burned for energy, release CO2 as a byproduct. This process contributes significantly to global greenhouse gas emissions, leading to climate change and environmental degradation. Carbon dioxide traps heat in the Earth's atmosphere, which raises global temperatures and disrupts weather patterns. Efforts to reduce carbon dioxide emissions include transitioning to renewable energy sources, improving energy efficiency, and adopting sustainable practices across various sectors to mitigate climate change impacts.