What we think of as “white flour” is really just refined flour, as opposed to whole, unrefined flour. In reality, “white flour” is flour that comes from white wheat, as opposed to red wheat. All-purpose flour is made from refined red wheat; whole wheat flour is made from unrefined red wheat; white whole wheat flour is made from unrefined white wheat. Make sense?
White whole wheat flour is great for people who don’t like the taste of whole wheat, because the white wheat has a milder taste than the red wheat, making the use of unrefined flour more palatable.