Biomass refers to organic material from living or recently living organisms, such as wood, waste, and alcohol fuels. It can be burned directly or processed to generate heat, electricity, or fuel. Benefits include being renewable, reducing pollution compared to burning fossil fuels, and providing cheaper energy. However, biomass is also inefficient relative to fossil fuels, and harvesting biomass on a large scale could damage forests. Effective use of biomass requires consideration of costs, environmental impacts, and logistics of collection and transportation.