What is the corret name for the types of valves used in a four stroke engine?

The correct name for the types of valves used in a four-stroke engine are intake valves and exhaust valves. The intake valves allow the air-fuel mixture to enter the combustion chamber during the intake stroke, while the exhaust valves enable the expulsion of combustion gases during the exhaust stroke. Together, these valves play a crucial role in the engine's intake and exhaust processes.