GPT and MBR disk

MBR is the standard partitioning scheme that's been used on hard disks since the PC first came out.

The GPT disk itself can support a volume up to 2^64 blocks in length. (For 512-byte blocks, this is 9.44 ZB - zettabytes. 1 ZB is 1 billion terabytes). It can also support theoretically unlimited partitions.

Windows restricts these limits further to 256 TB for a single partition (NTFS limit), and 128 partitions.

Being a part of the Extensible Firmware Interface (EFI) standard proposed by Intel to replace the outdated PC BIOS, it offers a number of crucial benefits:

  1. 1.Up to 128 primary partitions for the Windows implementation (only 4 in MBR)
  2. 2.The maximum allowed partition size is 18 exabytes (only 2 terabytes in MBR)
  3. 3.More reliable thanks to replication and cyclic redundancy check (CRC) protection of the partition table
  4. 4.A well defined and fully self-identifying partition format (data critical to the platform operation is located in partitions, but not in un-partitioned or hidden sectors as this is the case with MBR).