White glue is made from water, H2O, and polyvinyl acetate, a polymer of vinyl acetate which has the chemical formula C4H6O2. Polymers are made by chemically linking molecules together in chains of varying lengths, so the formula for polyvinyl acetate is technically (C4H6O2)n, where n can stand for any number.
Polyvinyl acetate is a rubbery, synthetic chemical with many industrial uses. When mixed with water, it becomes a milky white emulsion that forms a strong, flexible film that adheres to many kinds of surfaces when it dries. In addition to glue, polyvinyl acetate is also used to make latex paint, wallpaper adhesive and drywall primer.