What is the EFI partition?

When I install Windows 10 64-bit on a blank hard disk, as well as creating the C: drive, Diskmgmt.msc shows that an EFI partition is created. What is the EFI partition and why is it created?

Update:

When I install Windows 10 64-bit on a blank hard disk, as well as creating the C: drive, Diskmgmt.msc shows that an EFI partition is created. What is the EFI partition and why is it created?

Update:

Thanks for the answers so far. However, when I create a Live Linux USB pendrive, it has just one partition, and there is no EFI partition.

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  • 5 months ago
    Favorite Answer

    UEFI firmware provides the first stage bootstrap, which searches for the second stage bootstrap in a folder /boot/efi. The UEFI specification requires the file system holding this second stage to be a FAT based file system; however, Windows is normally installed in an NTFS filesystem, which a UEFI firmware may not support, although some computers may have firmware that can access NTFS file systems.

    To ensure that Windows can boot on any 64-bit UEFI computer, Microsoft introduced a separate EFI partition that has the required file system type, but is inaccessible to Windows. The second stage bootstrap in Microsoft's EFI partition can boot Windows from its NTFS partition.

    There is another reason why Microsoft use a separate EFI partition. If C: is BitLocker encrypted then there has to be a bootstrap that is not encrypted but can unlock and access the BitLocker encrypted C: file system.

    I hope this helps.

    • Bill5 months agoReport

      Thanks. That makes a lot of sense.

  • 5 months ago

    The EFI system partition (ESP) is a small partition formatted with FAT32, ususally 100MB, where stores the EFI boot loaders

  • Anonymous
    5 months ago

    Because Windows 10 by standard creates efi partitions to support hard drives larger than 2tb.

    With the legacy MBR, you can only go up to 2TB with the partition.

    Also EFI has better boot properties.

  • 5 months ago

    its windows 10 own recovery boot partition.STOP messing with windows and let it do its stuff.

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  • 5 months ago

    The EFI partition stores bootloaders and information needed for the bootloader to boot an operating system from another partition.

    A USB Flash drive wouldn't necessarily need a separate partition if it uses a file system UEFI natively supports, like FAT32. It also wouldn't need one if it was loaded by the CSM, a feature that loads legacy operating systems that use an MBR and boot sector.

    https://en.wikipedia.org/wiki/Unified_Extensible_F...

  • Anonymous
    5 months ago

    it's where the UEFI boot files are stored... windows usually makes this bigger than it needs to be and 64MB is plenty.

    This is different from the old way which used the MBR, and I believe MBR has drive size restrictions while GPT/UEFI doesn't.

    Do note that you CAN store the EFI's on the same partition that you intend to boot from, it's just cleaner to store them all in one partition if you have a multiboot system. (Many *Nix distros will try to install their own bootloaders in their own fashion and you can manually move and configure these as you see fit.)

    *Notes on the update*

    You should have an /boot/efi directory on the partition *Nix creates. Unlike the what the troll inclusive_disjunction says you do NOT need to have the EFI's on a separate partition. You CAN choose to mount a partition to that directory but the efi's do NOT need to be on a separate partition, neither to be found by the bios NOR to boot the operating system.

    • Richard
      Lv 7
      5 months agoReport

      "you CAN store the EFI's on the same partition that you intend to boot from" except that Windows normally uses NTFS and the UEFI specification requires the boot files to be in a FAT based partition.

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