Biofuel defined broadly is solid, liquid, or gas fuel consisting of, or derived from biomass. The more narrow definition used in this article is liquid or gas fuel derived from biomass and used as a fuel in transportation. Biomass used directly as a fuel is commonly called biomass fuel. Biofuel is considered an important means of reducing greenhouse gas emissions and increasing energy security by providing a viable alternative to fossil fuels.
Biofuels are commonly used throughout the world. The most common use for biofuels is automotive transport (E10 fuel). Essentially a biofuel can be produced from any short term carbon cycle organic compound; due to this there is a high variety of resources and therefore many types of biofuels. For a comprehensive chart of energy contents from different biofuels please see Energy content of Biofuel