All life originated from the cell-plant, animal and human life. The cell is the smallest living unit of the human body, which consists of trillions of cells. All cells perform most of their vital functions at thin, dynamic phospholipid double layers known as "membranes". These are the work surfaces on which a large proportion of the cell energy is generated and the majority of enzymatic activities take place. A cell is only as good as its membrane system, weakened or damaged membranes put the various cell functions at risk. As phospholipids are the foundation of all cell membranes and hence are the most essential building blocks of life the lipid composition of the cell membranes to a large extent determines the efficiency of every single cell and its range of capabilities. Since membrane phospholipid balance can be influenced by phospholipids in the diet, phospholipids are versatile membrane nutrients. Phospholipids are involved in a large number of metabolic processes in all tissues, blood cells and body fluids. These include: •Fat absorption and transport •Regulation of serum lipid levels •Cholesterol metabolism •Brain functions Liver functions Prostaglandin biosynthesis There are numerous scientific papers and clinical studies supporting the preventive and even therapeutic benefits of specific phospholipids classes. Commercial lecithins-the main source of phospholipids-historically have been used around the world as one of the first health food products, but-because of lack of purification technology and clear data on the benefits of defined phospholipids-with a vague and unclear application profile. This lecture shall explain the different phospholipids classes and their specific health related profile, both for food supplements and functional foods.