Defining the interface between the operating system and platform firmware
Background

The UEFI Specification was primarily intended for the next generation of IA architecture–based computers, and is an outgrowth of the "Intel® Boot Initiative" (IBI) program that began in 1998.
Intel's original version of this specification was publicly named EFI, ending with the EFI 1.10 version.
In 2005, The Unified EFI Forum was formed as an industry-wide organization to promote adoption and continue the development of the EFI Specification. Using the EFI 1.10 Specification as the starting point, this industry group released the following specifications, renamed Unified EFI.