UEFI glossary

B

• BDS – Boot Device Selection stage of the –> PI
• EBC Image – Executable EBC image in PE32 file format.
• EBC – –> EFI Byte Code.

E

• EFI – Extensible Firmware Interface. An interface between the operating system (OS) and the hardware platform firmware.
• EFI Byte Code – binary encoding of instructions generated by an EBC C compiler and linker. The EBC Image is executed by an interpreter.
• EFI File – A container with of a number of blocks that holds an image or a data file within a file system that complies to the UEFI specification.
• EFI Hard Disk – A hard disk that supports the EFI partitioning scheme GUID Partition.

P

• PI – Platform Initialization. The boot process on UEFI platforms.

U

• UEFI – Unified Extensible Firmware Interface. An interface between the operating system (OS) and the hardware platform firmware.
• UEFI Application – Modular code that may be loaded in the boot services environment (–> BDS), i.e. diagnostics or disaster recovery tools, an UEFI shell, or an OS bootloader. UEFI applications run outside the OS environment. After the UEFI applications is terminated, control is returned from the UEFI application to the platform firmware.
• UEFI Boot Service Driver – A UEFI driver that is loaded into boot services memory and stays resident until boot services terminate.
• UEFI Driver – Modular code that provides device support during the boot process, or provides platform services. UEFI drivers should not be confused with OS drivers that provide device support once the OS takes control of the platform.
• UEFI OS Loader – A UEFI application that is the first piece of operating system code loaded by the firmware to initiate the OS boot process. This code is loaded at a fixed address and then executed. The OS takes control of the system prior to completing the OS boot process by calling the interface that terminates all boot services.
• UEFI Runtime Services Driver – A UEFI driver that is loaded into runtime services memory and stays resident OS during runtime. UEFI Runtime Services Drivers provide access to UEFI to the OS.