Biomass - Wikipedia, the free encyclopedia: "Biomass is organic non-fossil material, collectively. In other words, biomass comprises the mass of all biological organisms, dead or alive, excluding biological mass that has been transformed by geological processes into substances such as coal or petroleum."
"In many ways biomass can be considered as a form of stored solar energy. The energy of the sun is 'captured' through the process of photosynthesis in growing plants."

Biofuel - Wikipedia, the free encyclopedia: "Biofuel is any fuel that derives from biomass — recently living organisms or their metabolic byproducts, such as manure from cows. It is a renewable energy source, unlike other natural resources such as petroleum, coal and nuclear fuels. The carbon in biofuels was recently extracted from atmospheric carbon dioxide by growing plants, so burning it does not result in a net increase of carbon dioxide in the Earth's atmosphere. As a result, biofuels are seen by many as a way to reduce the amount of carbon dioxide released into the atmosphere by using them to replace non renewable sources of energy."