The document discusses ring opening polymerization (ROP), which is a chain growth polymerization where cyclic monomers react to form polymer chains by opening their ring structures. There are three main types of ROP - radical, anionic, and cationic - depending on whether the reactive center is a radical, anion, or cation. Examples are given of monomers that can undergo each type of ROP, along with diagrams of the mechanisms. Common applications of ROP include nylon and biopolymers like polysaccharides.