Condensation polymerization is a chemical process where monomers join together to form a polymer while releasing small molecules, often water or methanol. This reaction typically occurs between two different functional groups, such as carboxylic acids and alcohols, leading to the formation of long-chain molecules. This type of polymerization is commonly used to create materials like polyesters and nylons. Unlike addition polymerization, which involves the simple linking of monomers without byproducts, condensation polymerization results in the loss of small molecules, making it a unique and important method in polymer chemistry.