Main Image: Ceramides are a family of lipid (group of naturally occurring molecules like fats, waxes, vitamins) molecules. A ceramide is composed of sphingosine (unsaturated hydrocarbon chain, which forms a primary part of cell membrane lipids) and a fatty acid. Ceramides are found in high concentrations within the cell (biological) membrane of cells. They are one of the component lipids that make up sphingomyelin (a type of lipid found in animal cell membrane), one of the major lipids in the lipid bilayer (thin membrane made up of 2 layers of lipid molecules).