Dry shampoo is a hair care product designed to absorb excess oil and refresh hair without the need for water. It typically comes in a spray or powder form and is applied directly to the scalp and hair. The main ingredients often include starch or alcohol, which help to soak up oil and give hair a cleaner appearance. Using dry shampoo can extend the time between regular washes, making it a convenient option for busy individuals. It is especially popular among those with oily hair or those who want to maintain their hairstyle for longer periods.