Retrofitting refers to the addition of new technology or features to older systems. An example of this is car customizing, where older vehicles are fitted with new technologies; power windows, cruise control, remote keyless systems, electric fuel pumps, etc. Particularly popular amongst auto enthusiasts is the process of correctly retrofitting OEM HID projectors into their outdated factory or aftermarket headlamps. The whole system is purchased off of such auction websites, where through careful assembly, the head lamps are opened and worked on. Retrofitting may also refer to the process of strengthening older buildings in order to make them earthquake resistant (See also Seismic retrofit). Principally retrofitting describes the measures taken in the manufacturing industry to allow new or updated parts to be fitted to old or outdated assemblies. The production of retrofit parts is necessary in manufacture when the design of a large assembly is changed or revised. If, after the changes have been implemented, a customer (with an old version of the product) wishes to purchase a replacement part then retrofit parts and assembling techniques will have to be used so that the revised parts will fit suitably onto the older assembly.
