Biogas is formed by the decomposition of animal dung, dry leaves, wet garbage in a biogas plant. This produces methane gas also called biogas. Biogas is a very cheap fuel option which meets the demand for cooking gas. Biogas is eco-friendly as it contains about 55% to 60% of methane and rest is carbon dioxide, hence, on combustion it does not produce harmful gases which cause pollution. Biogas is a fuel which is convenient to use and in addition to this it produces a very good manure as a side product of the process. Hence, biogas is an eco-friendly fuel.