Spark plugs deliver the high-voltage spark needed to ignite the air/fuel mixture within an internal combustion engine’s cylinders. These components thread into the cylinder head, positioning the electrode gap precisely within the combustion chamber. Modern spark plugs utilize a variety of electrode materials—including copper, platinum, and iridium—to enhance durability and service life. Heat ranges are carefully calibrated to maintain optimal operating temperature, preventing pre-ignition or fouling. Variations include projected-tip, recessed-tip, and J-hook designs to suit specific engine configurations and combustion chamber geometries.