Macromolecules are large, complex molecules that are essential for life. They are typically made up of smaller units called monomers, which bond together to form long chains. The four main types of macromolecules are proteins, carbohydrates, lipids, and nucleic acids. Each type plays a crucial role in biological processes, such as energy storage, structural support, and genetic information. Proteins are made of amino acids, while carbohydrates consist of sugar molecules. Lipids include fats and oils, which are important for energy storage and cell membranes. Nucleic acids, like DNA and RNA, are responsible for storing and transmitting genetic information. Together, these macromolecules are vital for the structure and function of living organisms.