Translations:BIOS Update/104/en
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The most prominent and widely used system has historically been the x86-based IBM PC compatible computer and its BIOS, which is why system firmware is sometimes called a BIOS even when it is not an IBM PC compatible BIOS, such as the AlphaBIOS of the DEC Alpha architecture or the OpenBIOS, an implementation of Open Firmware (IEEE-1275). EFI/UEFI, the successor of the PC BIOS, is also often called "(U)EFI-BIOS". Hence, the term "BIOS update" often refers to a system firmware update that is not really a PC BIOS.
The most prominent and widely used system has historically been the x86-based IBM PC compatible computer and its BIOS, which is why system firmware is sometimes called a BIOS even when it is not an IBM PC compatible BIOS, such as the AlphaBIOS of the DEC Alpha architecture or the OpenBIOS, an implementation of Open Firmware (IEEE-1275). EFI/UEFI, the successor of the PC BIOS, is also often called "(U)EFI-BIOS". Hence, the term "BIOS update" often refers to a system firmware update that is not really a PC BIOS.
This article focuses on the PC BIOS and early versions of its successor EFI/UEFI. On x86 (U)EFI System Class 1 and Class 2 have a BIOS compatible mode called "Legacy BIOS" or "CSM" (short for Compatiblity Support Module), which makes the UEFI behave like a PC BIOS. UEFI System Class 3, the standard since around 2020, no longer has a CSM.
On other firmwares the process of updating the system firmware may have similarities, but can also be completely different.