Ethanol is an organic chemical compound. It is a simple alcohol with the chemical formula C ₂H ₆O. Its formula can be also written as CH ₃−CH ₂−OH or C ₂H ₅OH, and is often abbreviated as EtOH. Ethanol is a volatile, flammable, colorless liquid with a slight characteristic odor. Ethanol is a common ingredient in many cosmetics and beauty products. It acts as an astringent to help clean skin, as a preservative in lotions and to help ensure that lotion ingredients do not separate, and it helps hairspray adhere to hair.