Methanol is the simplest alcohol, being only a methyl group linked to a hydroxyl group. It is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to that of ethanol (drinking alcohol). However, unlike ethanol, methanol is highly toxic and unfit for consumption. At room temperature, it is a polar liquid. It is used as an antifreeze, solvent, fuel, and as a denaturant for ethanol. It is also used for producing biodiesel by transesterification reaction.
Methanol is produced naturally in the anaerobic metabolism of many varieties of bacteria and is commonly present in small amounts in the environment. As a result, the atmosphere contains a small amount of methanol vapor. However, in only a few days, atmospheric methanol is oxidized by sunlight to produce carbon dioxide and water.