Write down the main types of polymerization.

(N/A) There are two broad types of polymerization reactions:
$(a)$ Addition or chain growth polymerization: In this type,monomers containing double or triple bonds add together to form polymers without the loss of any small molecules.
$(b)$ Condensation or step growth polymerization: In this type,monomers containing bifunctional or polyfunctional groups react with each other,usually with the elimination of small molecules like $H_2O$,$HCl$,or $NH_3$.