Piston rings are critical components found in internal combustion engines and hydraulic systems, forming a seal between the piston and cylinder walls to contain combustion gasses or hydraulic fluid and regulate oil consumption. These rings create a tight fit within the cylinder bore, preventing leakage while allowing for smooth reciprocating motion of the piston. By maintaining proper compression, reducing friction, and facilitating heat transfer, piston rings contribute to engine efficiency, performance, and durability in automotive, marine, and industrial applications.