Tapioca Starch and Tapioca Flour are the same thing. Tapioca Starch comes from the root of the cassava plant. It basically the same thing as Tapioca Pearls but has been ground into a fine powder. Tapioca Starch/Flour adds structure to gluten-free baking. It also helps give things a chewy and/or crisp texture, especially in things like cookies and cakes. It can also be used as a thickener in sauces and gravy.