Remember the days when you didn't need anything but a muffler and a tailpipe. And when your tailpipe rusted you just replaced it with a Campbell soup can?
Then we approached the era of air quality and low emission standards. This resulted in the use of catalytic converters, as some hillbillies refer to them as "Cadillac" converters. The catalytic converter is housed in a box on the vehicle's exhaust system. It cleans up exhaust gases before they are expelled from the exhaust pipe.