Hair: people use this as natural dry shampoo to control oily roots, which is so smart cause most dry shampoos are actually really bad for your hair
Skin: controls oil secretion throughout the day, similar to blotting paper and reduces the appearance of pores
Makeup: as a setting powder for concealer, foundation etc. if you want a matte and stable finish. It leaves a slight whiteness but generally not noticeable. It also has a "blur effect" on top of makeup to leave a more soft, smooth finish on your skin.