
The U for Unified was added to the name at this point. Later, Intel passed control over the EFI specification to the UEFI Forum and they continued developing newer versions of the specification. It was first seen in the wild on Itanium (ia64) machines and that's where Debian's first support started too. UEFI started life as Intel's EFI specification. See Grub2#UEFI_vs_BIOS_boot for a comparison of BIOS and UEFI boot via GRUB, the default bootloader in Debian. It's a standard specification for the firmware interface on a computer, and it has been implemented by multiple vendors on various platforms. (U)EFI stands for (Unified) Extensible Firmware Interface. Firmware does not support setting boot variables.Firmware has run out of space to write boot variables.



