- Polymers are large molecules made up of repeating smaller units called monomers. - Natural polymers are those produced by living organisms. Examples include polysaccharides (like cellulose and starch), proteins (like silk and wool), and nucleic acids (like DNA and RNA). - Synthetic polymers are man-made through chemical processes. Examples include plastics (like polyethylene, polypropylene, polystyrene, polycarbonate - Lexan), synthetic fibers (like nylon, polyester, Kevlar), and synthetic rubbers.