This document discusses the four main types of organic macromolecules: lipids, proteins, carbohydrates, and nucleic acids. Lipids are made up of carbon, hydrogen, and some oxygen and serve functions like energy storage, insulation, cushioning organs, and acting as hormones. Proteins contain carbon, hydrogen, oxygen, and nitrogen and make up things like hair, skin, and nails. Carbohydrates contain sugars and starches. Nucleic acids include DNA and RNA, with DNA containing an organism's genetic code and RNA assisting in protein synthesis.