1.) Machines, which separate by shape, remove barley, oats and small seeds. Gravity separation removes stones and, throughout the cleaning process, air currents lift off dust and chaff.
2.)Semolina flour differs from white flour in the way it's processed and the type of wheat that's used. Semolina is made with grooved steel rollers. The rollers crack the starch of wheat kernels into coarse pieces which is then ground into flour. The starch itself is the semolina.
3.) Whole Wheat flour or Whole grain flour is milled from the complete seed and nothing is removed. This adds not only fiber but all the minerals and vitamins in the different layers of the wheat seed.