A local bus standard developed by Intel Corporation (Peripheral Component Interconnect or PCI); a printed circuit board that acts as an interface to connect several connectors in parallel to each other, so that each pin of each connector is linked to the same relative pin of all the other connectors, forming a computer bus. The board is used as a backbone to connect several printed circuit boards together to make up a complete computer system--in this case, the XI system. A backplane generally is differentiated from a motherboard by the lack of onboard processing power; due to its greater reliability, a backplane normally is preferred to cables.