PCI is a local computer bus for attaching hardware devices in a computer. PCI is the initialism for Peripheral Component Interconnect and is a part of PCI Local Bus standard. PCI bus supports the functions found on a processor bus but in a standardized format that is independent of any particular processor's native bus. Devices connected to the PCI bus appear to a bus master to be connected directly to its own bus and are assigned addresses in the processor's address space. It is a parallel bus, synchronous to a single bus clock.