Alcohol is a natural product which is produced by fermentation of barley (beer) and grapes (wine).

This natural process of fermentation stops at about 15% alcohol. This is called weak alcoholic beverage. By heating and cooling of weak alcoholic beverages (distilled) higher alcohol percentages may occur, booze. Beer is 5% alcohol, wine 12% and spirits, such as gin 35%. In addition to beer, wine and distilled there are more types of drinks on the market. Among young people especially the so-called popular mixed drinks, as well as shooters and alcopops. Chemical formula of alcohol (ethanol): C 2 H 5Oh.