The document defines and compares different types of lipids, including triglycerides, waxes, steroids, phospholipids, proteins, and nucleic acids. It describes the elemental composition, examples, subunits, and functions of each type. Triglycerides, for example, are composed of carbon, hydrogen, and oxygen, with examples including fats and oils. Their subunits are three fatty acids and glycerol, and their functions include energy storage and insulation.