This document summarizes information about shampoos, including their introduction, requirements, classifications, types, mechanisms, compositions, formulations, evaluations, containers, specific examples, and references. Shampoos are preparations containing surfactants that remove dirt, grease, and debris from hair without harming the scalp. They are generally classified based on their base as soap-based or detergent-based shampoos. Common types include liquid, powder, lotion, cream, and aerosol shampoos. Shampoos work by allowing water to penetrate hair and dissolve/remove oils and dirt. Their formulations typically contain surfactants, conditioning agents, thickeners, preservatives,