Unified Extensible Firmware Interface ( UEFI, / ˈ juː ɪ f aɪ/ or as an acronym) is a specification that defines the architecture of the platform firmware used for booting the computer hardware and its interface for interaction with the operating system. They can use different I/O protocols, but SPI is the most common. The UEFI implementation is usually stored on a NOR-based EEPROM that is located on the mainboard.
