When a car rolls off the production line, the parts going into it need to meet a certain standard of quality, performance and reliability to ensure the best driving experience for the buyer. OE (or original equipment) refers to the parts put into a new car, whereas OEM means the manufacturer of these parts, who generally produce them from designs by the manufacturer of the car. Famous OE Manufacturers include Bosch, Hella, MANN Filter and SuperPro, meaning purchasing from any of these companies guarantees the same level of performance from the part as you would get if the car was new out of the factory.