So, here ya go people:
Wheat flour is made from grains of wheat berries. Wheat berries are made of three parts: the germ, the endosperm, and the bran.
The wheat germ is the part that sprouts: it contains all of the nutrients and minerals that the berry needs to live, including wheat germ oil, which is what helps our bodies absorb vitamins that aren't water soluble. The endosperm is made of mostly starch and protein; it's what feeds the germ. The bran is the outer hull where all the fiber is.
Whole grain flour is made from the entire grain- all ground up. It can be coarse and grainy, good for bread baking, or ground super fine for things like cakes & cookies.
If you look at the baking aisle in the grocery store, you mostly see bags of "All-Purpose Flour" lining the shelves. This flour is made from wheat grains that have been milled to remove the bran and germ, so the flour is made only from the endosperm. By removing the bran and germ, you take away virtually all of the nutritional value of wheat: the fiber, the wheat germ oil, and that nutrients and minerals in the germ. What you have left is just starchy, powdery white flour that our bodies just break down into sugar. Because white flour doesn't contain any of the oils from the wheat germ, it has a much longer shelf life, which is why it became so popular commercially- it could be bagged and stored for more than a year before going rancid.
True whole grain wheat flour is a totally living food. Once the grain is ground, it exposes the inner parts to air and oxidizes, and it has a very short shelf life. Within 72 hours it loses its nutritional value, and within a week it can become rancid from oxidation.
So anyway, all of this is what led me into grinding my own flour fresh. It's packed with all the nutrients and vitamins that flour is supposed to have, and the taste of fresh bread with fresh flour is just unbeatable. So I buy organic wheat berries from Stutzman's Amish Farms in Ohio and grind them in a flour mill. If you want to try this yourself, you don't necessarily have to buy a mill. You can use a coffee grinder, a baby food grinder, etc. Kitchen Aid mixers also come with a flour grinding attachment. And you can get wheat berries like I do from the Co-Op, Whole Foods, or the Raisin Rack.
Okay, that is a LOT of info. If you want to read more, check out some of these websites: