Biphenyl is an organic compound consisting of two connected benzene rings. Its chemical formula is C12H10, and it appears as a colorless solid at room temperature. Biphenyl is commonly used in the production of polychlorinated biphenyls (PCBs), which were historically used as coolants and insulating fluids in electrical equipment. In addition to its industrial applications, biphenyl serves as a heat transfer agent and is found in some chemical synthesis processes. It can also be used as a solvent in various chemical reactions. Due to its potential environmental and health impacts, the use of biphenyl and its derivatives is regulated in many countries.