The document discusses biogas, which is a mixture of methane and carbon dioxide produced from the decomposition of organic waste. Biogas is formed through anaerobic digestion by bacteria as it breaks down biomass in the absence of oxygen. It has various applications such as cooking, drying, cooling, heating, and can also be used to produce electricity, methanol, and steam. Additionally, compressed biogas can fuel vehicles. The advantages of biogas include use as organic fertilizer, pollution control, and providing an eco-friendly fuel alternative to help control global warming.