Ceramide NP, Ceramide NS, Ceramide EOS, Ceramide EOP, Ceramide AP, Caprooyl Phytosphingosine, Caprooyl Sphingosine - Ceramides are lipids naturally found in the stratum corneum, the outermost skin layer, which is composed of dead cells and acts act as a protective barrier. They are the major structural components of the epidermal permeability barrier.  The main function of ceramides within the skin is to control the growth and differentiation of cells when they are in the process of becoming specialized.