Diamines are organic compounds that contain two amine groups, which are functional groups characterized by a nitrogen atom bonded to hydrogen atoms or carbon chains. They are often used in the production of various chemicals, including dyes, pharmaceuticals, and polymers. Common examples of diamines include ethylenediamine and hexamethylenediamine. These compounds play a crucial role in the synthesis of materials like nylon and other synthetic fibers. Diamines can also be involved in biochemical processes, serving as building blocks for proteins and other essential molecules in living organisms. Their versatility makes them important in both industrial and biological applications.