MBR / GPT / UEFI – WHAT’S IT ALL ABOUT?

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MBR was first introduced with IBM PC DOS 2.0 in 1983 (Master Boot Record) contains the initial boot loader.

  • The boot loader is a small bit of code that generally loads the larger boot loader from another partition on a drive.
  • MBR only works with disks up to 2 TB in size and only supports up to 4 primary partitions.
  • On an MBR disk, the partitioning and boot data is stored in one place. If this data is overwritten or corrupted, you’re in trouble.

GPT is a newer standard that’s gradually replacing MBR.

  • GPT allows for a nearly unlimited number of partitions.
  • GPT stores multiple copies of this data across the disk, so it’s much more robust and can recover if the data is corrupted.
  • If you try to manage a GPT disk with an old tool that can only read MBRs, it will see a single partition that extends across the entire drive (Protective MBR).

UEFI replaces the clunky old BIOS with something more modern. GPT needs UEFI,.

  • Windows can only boot from GPT on UEFI-based computers running 64-bit versions of Windows 10, 8, 7, Vista, and server versions.
  • Linux has built-in support for GPT. Apple’s Intel Macs no longer use Apple’s APT (Apple Partition Table) scheme and use GPT instead.
  • UEFI replaces the traditional BIOS on PCs. There’s no way to switch from BIOS to UEFI on an existing PC.

MBR

GPT

BIOS / UEFI