This lecture covers the critical micelle concentration (CMC) of hexane, the influence of salt on CMC, the structure of aggregates determined by intermolecular forces, the packing parameter of amphiphiles, and the shapes of aggregates. It also discusses the aspect ratio's impact on aggregate shape, the packing parameter of spheres, examples of aggregates like sodium dodecyl sulfate, and methods to make elliptical micelles spherical. Furthermore, it explores the theory of detergent action, vesicles as delivery vehicles for hydrophobic ingredients, and the mobility and diffusion of phospholipids in bilayers.