Manure is organic matter, mostly derived from animal feces except in the case of green manure, which can be used as organic fertilizer in agriculture. Manures contribute to the fertility of the soil by adding organic matter and nutrients, such as nitrogen, that are trapped by bacteria in the soil. Higher organisms then feed on the fungi and bacteria in a chain of life that comprises the soil food web. It is also a product obtained after decomposition of organic matter like cow dung which replenishes the soil with essential elements and add humus to the soil.
Manure is a faecal matter of cow,buffalo n ox 
it can be used as best organic natural fertiliser.the urea present in nourishes the soil so that fertility of the soil can be adds nitrogen to the soil.with the help animal manure we can produce biogas