Cerium is widely used in catalytic converters in automotive exhaust systems to reduce harmful emissions by helping convert carbon monoxide and hydrocarbons into less toxic substances like carbon dioxide and water vapor. It is a key component in fluid catalytic cracking (FCC) catalysts used in petroleum refineries to produce gasoline from crude oil. Cerium oxide serves as a polishing agent for glass, optical lenses, and semiconductor materials due to its effective abrasive properties. In glass production, it also helps reduce light reflection and provides protection against ultraviolet radiation. It is used in self-cleaning ovens, where it helps combust food residues. In addition, cerium compounds are used in the production of phosphors for lighting and display technologies, and as a stabilizer in flat-panel displays and fluorescent lamps. Cerium-doped materials are employed in solid oxide fuel cells to enhance ionic conductivity. In the metal industry, cerium is alloyed with other metals to improve corrosion resistance and strength, especially in high-temperature applications. Historically, it was used in gas lamp mantles to produce bright flames. Its ability to shift between oxidation states makes it valuable in redox reactions, and ongoing research explores its applications in batteries and advanced ceramics, as well as hydrogen storage materials.