The following table defines terms used in this document. See the glossary in the UEFI Specification for definitions of additional terms.
| Term | Definition |
|---|---|
| '' | Element of an enumeration. Type INTN. |
| ACPI | Advanced Configuration and Power Interface. |
| ANSI | American National Standards Institute. |
| API | Application programming interface. |
| ASCII | American Standard Code for Information Interchange. |
| ATAPI | Advanced Technology Attachment Packet Interface. |
| BAR | Base Address Register. |
| BBS | BIOS Boot Specification. |
| BC | Base Code. |
| BEV | Bootstrap Entry Vector. A pointer that points to code inside an option ROM that directly loads an OS. |
| BIOS | Basic input/output system. |
| BIS | Boot Integrity Services. |
| BM | Boot manager. |
| BOOLEAN | Logical Boolean. 1-byte value containing a 0 for FALSE or a 1 for TRUE. Other values are undefined. |
| BOT | Bulk-Only Transport. |
| BS | EFI boot services table or EFI Boot Service(s). |
| CBI | Control/Bulk/Interrupt Transport. |
| CBW | Command Block Wrapper. |
| CHAR16 | 2-byte character. Unless otherwise specified, all strings are stored in the UTF-16 encoding format as defined by Unicode 2.1 and ISO/IEC 10646 standards. |
| CHAR8 | 1-byte character. |
| CID | Compatible ID. |
| CONST | Declares a variable to be of type const. This modifier is a hint to the compiler to enable optimization and stronger type checking at compile time. |
| CR | Containing Record. |
| CRC | Cyclic Redundancy Check. |
| CSW | Command Status Wrapper. |
| DAC | Dual Address Cycle. |
| DHCP4 | Dynamic Host Configuration Protocol Version 4. |
| DID | Device ID. |
| DIG64 | Developer's Interface Guide for 64-bit Intel Architecture-based Servers. |
| DMA | Direct Memory Access. |
| EBC | EFI Byte Code. |
| ECR | Engineering Change Request. |
| EFI | Extensible Firmware Interface. |
| EFI_EVENT | Handle to an event structure. Type VOID *. |
| EFI_GUID | 128-bit buffer containing a unique identifier value. Unless otherwise specified, aligned on a 64-bit boundary. |
| EFI_HANDLE | A collection of related interfaces. Type VOID *. |
| EFI_IP_ADDRESS | 16-byte buffer aligned on a 4-byte boundary. An IPv4 or IPv6 internet protocol address. |
| EFI_Ipv4_ADDRESS | 4-byte buffer. An IPv4 internet protocol address. |
| EFI_Ipv6_ADDRESS | 16-byte buffer. An IPv6 internet protocol address. |
| EFI_LBA | Logical block address. Type UINT64. |
| EFI_MAC_ADDRESS | 32-byte buffer containing a network Media Access Controller address. |
| EFI_STATUS | Status code. Type INTN. |
| EFI_TPL | Task priority level. Type UINTN. |
| EISA | Extended Industry Standard Architecture. |
| FAT | File allocation table. |
| FIFO | First In First Out. |
| FPSWA | Floating Point Software Assist. |
| FRU | Field Replaceable Unit. |
| FTP | File Transfer Protocol. |
| GPT | Guided Partition Table. |
| GUID | Globally Unique Identifier. |
| HC | Host controller. |
| HID | Hardware ID. |
| I/O | Input/output. |
| IA32 | 32-bit Intel architecture. |
| IBV | Independent BIOS vendor. |
| IDE | Integrated Drive Electronics. |
| IEC | International Electrotechnical Commission. |
| IHV | Independent hardware vendor. |
| IN | Datum is passed to the function. |
| INT | Interrupt. |
| INT16 | 2-byte signed value. |
| INT32 | 4-byte signed value. |
| INT64 | 8-byte signed value. |
| INT8 | 1-byte signed value. |
| INTN | Signed value of native width. (4 bytes on IA32, 8 bytes on X64 and IPF) |
| IPF | Itanium processor family. |
| Ipv4 | Internet Protocol Version 4. |
| Ipv6 | Internet Protocol Version 6. |
| ISA | Industry Standard Architecture. |
| ISO | Industry Standards Organization. |
| iSCSI | SCSI protocol over TCP/IP. |
| KB | Keyboard. |
| LAN | Local area network. |
| LUN | Logical Unit Number. |
| MAC | Media Access Controller. |
| MMIO | Memory Mapped I/O. |
| NIC | Network interface controller. |
| NII | Network Interface Identifier. |
| NVRAM | Nonvolatile RAM. |
| OEM | Original equipment manufacturer. |
| OHCI | Open Host Controller Interface. |
| OpROM | Option ROM. |
| OPTIONAL | Datum that is passed to the function is optional, and a NULL may be passed if the value is not supplied. |
| OS | Operating system. |
| OUT | Datum is returned from the function. |
| PCI | Peripheral Component Interconnect. |
| PCMCIA | Personal Computer Memory Card International Association. |
| PE | Portable Executable. |
| PE/COFF | PE32, PE32+, or Common Object File Format. |
| PNPID | Plug and Play ID. |
| POST | Power On Self Test. |
| PPP | Point-to-Point Protocol. |
| PUN | Physical Unit Number. |
| PEI | Pre-boot Execution Environment. |
| PXE BC (or PxeBc) | PXE Base Code Protocol. |
| QH | Queue Head. |
| RAID | Redundant Array of Inexpensive Disks. |
| RAM | Random access memory. |
| ROM | Read-only memory. |
| RT | EFI Runtime Table and EFI Runtime Service(s). |
| SAL | System Abstraction Layer. |
| SCSI | Small Computer System Interface. |
| SIG | Special Interest Group. |
| S.M.A.R.T. | Self-Monitoring Analysis Reporting Technology. |
| SMBIOS | System Management BIOS. |
| SMBus | System Management Bus. |
| SNP | Simple Network Protocol. |
| SPT | SCSI Pass Thru. |
| ST | EFI System Table |
| STATIC | The function has local scope. This modifier replaces the standard C static key word, so it can be overloaded for debugging. |
| TCP/IP | Transmission Control Protocol/Internet Protocol. |
| TD | Transfer Descriptor. |
| TPL | Task Priority Level. |
| UART | Universal Asynchronous Receiver-Transmitter. |
| UHCI | Universal Host Controller Interface. |
| UID | Unique ID. |
| UINT16 | 2-byte unsigned value. |
| UINT32 | 4-byte unsigned value. |
| UINT64 | 8-byte unsigned value. |
| UINT8 | 1-byte unsigned value. |