Thank you for clearing that up for me.mcneon said:It's "Original Equipment Manufacturer." The label refers to the parts originally used in production by the car maker or available from dealers. OEM parts can be made directly by the automaker or by third-party companies and supplied to the automaker.
For example, Honda might build its own mufflers, or a company like Walker Mufflers might have an OEM contract to supply mufflers to them. They would build these to Honda specs and with the Honda logo and part number and supply them to Honda. Either type of part would be known as an OEM part.
Non-OEM parts are usually referred to as "aftermarket" parts.