Involves using tools, like brushes, sponges, loofahs, or abrasive scrubs, that create enough friction to loosen and slough away dead skin cells, debris, and oils.
Uses chemicals such as hydroxy acids, retinol, and enzymes, to aid in cell turnover and cause the superficial epidermal layers to exfoliate sans friction.
Over-exfoliating can be counterproductive for mature skin, slowing cell turnover, causing inflammation (which accelerates skin aging), and stripping skin of necessary natural oils.