Polymerizations refer to the process of linking monomer units to produce a long chain of macromolecules. There are many synonyms for polymerization depending on the type of reaction and the resulting polymer. One synonym is condensation polymerization which describes the buildup of a polymer by releasing small molecules such as water, alcohol, or ammonia. Addition polymerization refers to the process of adding monomers together without losing any small molecules. Radical polymerization involves the use of initiators to start the reaction. Other synonyms include cationic polymerization, anionic polymerization and emulsion polymerization. These terms can be used interchangeably to describe the same process of creating complex macromolecules from simple monomers.