Polyols or, as they are sometimes called, polyhydric alcohols, are compounds containing more than one hydroxyl group (–OH). Each hydroxyl is attached to separate carbon atoms of an aliphatic skeleton. This group includes glycols, glycerol, and pentaerythritol and also such products as trimethylolethane, trimethylolpropane, 1,2,6-hexanetriol, sorbitol, inositol, and poly(vinyl alcohol).