EDKII
The EFI Developer Kit (EDK) is an Open Source release of the Framework Foundations, defined in the Framework Core Interface Specifications (CIS), plus a set of sample drivers and three sample targets implemented for the Nt32, Unix, and DUET platforms.In addition to Open Sourcing the Framework Foundation code, the EDK allows for the development, debugging, and testing of EFI and DXE drivers, Option ROMs, and pre-Boot applications. To solve customer feedback exposed by using EDK, Intel started a remodeling plan now known as EDKII. It focuses on how to make it easy for customers to write a specific kind of module, to port and to customize modules to a platform.