Glycerol, also known as glycerin, is a chemical with the formula C4H8O3. It is a simple polyol compound that is colorless, odorless, and viscous. Glycerol has many uses including in pharmaceuticals, soaps, explosives, and as a sweetener. It is also used as an embalming fluid and in antifreeze. Glycerol can irritate eyes, skin, and respiratory systems in its concentrated form.