The word “varnish” is a generic term used for any type of wood finish shellac, including polyurethane and lacquer, but it technically refers to a specific combination of solvents, resins and oils. Varnish has been about for centuries, in the start, the formula consisted of alcohol and wood sap while polyurethane is a comparatively modern invention which had made from synthetics. Similarly, shellac and Lacquer other ingredients which are generally used to achieve a specific look.
