Ethanol , also called alcohol , ethyl alcohol , and drinking alcohol , is a chemical compound , a simple alcohol with the chemical formula C
5 OH . Its formula can be written also as CH
3 − CH
2 − OH or C
5 − OH (an ethyl group linked to a hydroxyl group), and is often abbreviated as EtOH . Ethanol is a volatile , flammable , colorless liquid with a slight characteristic odor. It is a psychoactive substance and is the principal type of alcohol found in alcoholic drinks .