Shampoo that only washes dirt out of your hair isn’t doing your hair any good in the long run. Modern shampoo formulas focus on specific areas of your hair that need help. From dry scalp, to dead ends, to product build-up and beyond, there is a shampoo for everything. Maintenance shampoo is always at the top of the list, as it does the job of keeping your hair in tip-top shape. There are different types of maintenance shampoos, including ones that will strengthen hair, rid of product build-up, and repair colored hair. Here's how to know which one is right for you.