What is tannin? Does red wine have a higher level of tannin than white wine?

Tannin is a natural compound found in wine. It comes from the skins, stems, and pips of the grapes, as well as from the wooden barrels used to age wine.
Red wine does have a higher level of tannin than white wine. This in part accounts for its ability to improve with age.
(what the heck is a grape pip?? "A grape seed extract that is a potent source of proanthocyanidins/pycnogenols and is a very powerful antioxidant")