PCI

PCI is an acronym that can refer to several standards in computing and finance. The most common usages are Peripheral Component Interconnect, PCI Express, and the Payment Card Industry Data Security Standard.

Peripheral Component Interconnect (PCI) is a former computer bus standard used to connect motherboard components with add-on cards. Introduced in the 1990s, PCI defined a parallel bus that carried data between the CPU, memory, and devices such as network and sound cards. It supported bus mastering and 32- or 64-bit data transfers. PCI was largely superseded by PCI Express and is now primarily of historical interest, though it influenced later designs and terminology, with PCI-SIG continuing to maintain related specifications.

PCI Express (PCIe) is the current bus standard that replaces PCI. It uses high-speed serial point-to-point links and supports scalable lane configurations (for example, x1, x4, x8, and x16). PCIe provides higher bandwidth and flexibility across multiple generations, while preserving software compatibility. It is widely used to connect graphics cards, solid-state drives, network adapters, and other peripherals in modern desktop and server systems.

Payment Card Industry Data Security Standard (PCI DSS) is a security framework established by major card brands to protect cardholder data. It applies to organizations that store, process, or transmit such information. PCI DSS outlines twelve requirements focused on network security, data protection, access control, monitoring, and maintaining secure systems. Compliance is validated through self-assessment or independent audits, and non-compliance can result in penalties or loss of ability to process card transactions.