Deepa is a traditional fuel source in rural parts of India made from cow dung that has been dried and molded into a circular shape. It is primarily used as a fuel for cooking, heating, and lighting purposes. Cow dung deepa is believed to have several benefits, including being an eco-friendly and renewable source of fuel, producing less smoke and harmful gases than other fuel sources, and having anti-bacterial and anti-fungal properties. In Hindu culture, cow dung is considered sacred and is often used in religious ceremonies and rituals.