An exhaust system is used to guide reaction exhaust gases away from a controlled combustion inside an engine or stove. The entire system conveys burnt gases from the engine and includes one or more exhaust pipes.
source/image(PrtSc): Automotive Basics
The exhaust system is made up of several components that work together to reduce exhaust noise and provide a conduit for exhaust gases to exit the engineExhaust gases are collected from the cylinder head in the engine by an exhaust manifold. The exhaust manifold acts as a funnel diverting exhaust gases from all cylinders of the engine then releases them through a single opening often referred to as the front pipe.
These exhaust gases then travel through a catalytic converter which removes harmful elements including carbon monoxide and hydrogen monoxide which are converted into inert gases.The gases then pass through a silencer or muffler.An exhaust pipe must be carefully designed to carry toxic and/or noxious gases away from the users of the machine.
Indoor generators and furnaces can quickly fill an enclosed space with poisonous exhaust gases such as hydrocarbons, carbon monoxide and nitrogen oxides, if they are not properly vented to the outdoors.For the internal combustion engine it is important to have the exhaust system “tuned” (refer to tuned exhaust) for optimal efficiency./wikipedia