Biodiesel is an alternative fuel similar to conventional or fossil diesel. Biodiesel is a renewable, biodegradable fuel manufactured domestically from vegetable oils, animal fats, tallow and waste cooking oil or recycled restaurant grease. The process used to convert these oils to Biodiesel is called transesterification. Biodiesel meets both the biomass-based diesel and overall advanced biofuel requirement of the Renewable Fuel Standard. Biodiesel can be used alone, or blended with petrol diesel in any proportions. Its good for the engine and less polluting. Biofuel is good for the environment.