Ethanol - the most widely used biofuel today. It can be used either as an alternative fuel or as an octane-boosting, pollution-reducing additive to gasoline. Ethanol is an alcohol fuel made from sugars and starch found in plants.

In the United States, ethanol is primarily produced from the starch contained in grains such as corn, through a fermentation and distillation process that converts starch to sugar and then to alcohol.

Currently, a majority of ethanol is made from corn, but new technologies are being developed to make ethanol from other agricultural and forestry resources.