Have your clothing, sheets, and towels been look dull and drab after washing? If you add a cup of kosher salt to your wash it helps dissolve  stain-causing grime, refreshes whites, and helps dyes set into fabrics. It will also keep dark colors from bleeding into the laundry water. If you also have yellow sweat stains on your whites, add a laundry scoop of baking soda along with the salt to make those shirts look like new!