What is the purpose of a catalytic converter, and what is the reaction equation of a process that it catalyses?

Catalytic converters are used in motor vehicles.They catalyse the conversion of potentially harmful gases produced in the combustion of motor fuel, into less harmful gases.The reactants for such a conversion are nitrous oxides and carbon monoxide, and the products CO2 and N2.An example full reaction equation is: 2NO + 2CO --> N2 + 2CO2