Original Equipment Manufacturer. An original equipment manufacturer, or OEM, manufactures products or components that are purchased by another company and retailed under that purchasing company's brand name.[OEM refers to the company that originally manufactured the product. When referring to automotive parts, OEM designates a replacement part made by the manufacturer of the original part. Confusing and contradictory definitionsThough incorrect, the term OEM may also counter-intuitively refer to a manufacturer that purchases for use in its own products a component made by a second company. Under this definition, if Apple purchases optical drives from Toshiba to put in its computers, Toshiba is the OEM, and would classify the transaction as an "OEM sale". Instead of OEM, companies may label themselves resellers. Companies who buy parts and then resell those parts with some amount of additional value added along the way (such as assembly, customer support, or continued maintenance) may be better termed value-added resellers (VARs) or resellers.