Wheat flour is the flour directly ground by wheat, with the outer skin and middle part of wheat, which is coarse grains. In fact, this kind of flour should be called whole wheat flour, which contains all the components of wheat, and the bran is less removed (or not removed at all), and the embryo, endosperm and bran are mixed together and ground. Those little brown flakes you see in the whole wheat flour you buy are wheat bran. Whole wheat flour better retains a variety of nutrients and active ingredients in wheat.