UEFI

Technical specification for firmware architecture

Unified Extensible Firmware Interface or UEFI is a specification for the firmware architecture of a computing platform. When a computer is powered on, the UEFI implementation typically runs first, before the operating system or any other program is loaded. Examples include AMI Aptio, Phoenix SecureCore, TianoCore EDK II, and InsydeH2O. UEFI replaces the BIOS that was present in the boot ROM of all personal computers that are IBM PC compatible, although it can provide backwards compatibility with the BIOS using CSM booting.

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