Genuine (OEM)
The same part the factory fitted, in the manufacturer’s box. Safest choice for electronics, sensors, engine internals and anything with a tight tolerance.
Aftermarket
Made by a brand such as Bosch, Brembo or Mann-Filter to the same specification. Often the OEM supplier itself. Good value for filters, brakes, bulbs, batteries and suspension.
Used, tested
Removed from another car, tested and sold with a short warranty. Sensible for body panels, mirrors, wheels and discontinued parts. Avoid used parts for brakes, belts, bearings and electronics.
