What is meant by the term "cell renewal" and why is that good for my complexion?

The cells of the top layer of skin, the epidermis, are in a constant process of regeneration or cell renewal. New cells are formed at the base of the epidermis and make their way to the surface where they are shed or exfoliated. Shedding dead skin stimulates the formation of new skin cells. Thus, sloughing off dead skin cells helps to speed up the process of cell renewal and reveal softer, clearer, more even-toned skin. For both clearer skin and anti-aging benefits, try using a serum that contains both alpha hydroxy acids and beta hydroxy acid, also known as salicylic acid.