"Washing your hair doesn't always need to involve wringing out your hair. Read on to explore an alternative age-old invention: dry shampoo.
Dry Shampoo: Don't Lather. Don't Rinse. Repeat.
Whereas wet shampoo uses soap and water to lift dirt and oil from the scalp, dry shampoo instead absorbs that oil, much like a sponge, and carries it away as you brush your hair. The catch: it only removes the oil, leaving other kinds of buildup such as dirt, hairspray residue, or hats intact. Because of this, dry shampoo shouldn't be used to clean the hair—only to make it less greasy (and thus more manageable) in a pinch, whether you’re camping in the woods or rushing through your morning routine.
Although dry shampoo seems like a modern marvel, the use of powders and clays to absorb oil from the scalp has existed for centuries. In fact, many homebrew methods exist to make your own dry shampoo, using such ingredients as corn meal, large-grain salt, and semolina flour. Still, professional formulas have a few advantages, with a variety of applications—from loose powders to aerosol sprays—and colors to match any shade of hair."