GUID Partition Table (GPT) is a modern way to save partition information. It was developed to overcome the limitations of MBR. MBR is a classic way to save partition information. MBR only supports hard disks up to 2 TB.
With the increasing use of disks larger than 2TB, a new partitioning standard called GUID (Globally Unique Identifiers) was developed and integrated into the UEFI firmware. It is called GPT (GUID Partition Table). It uses a 4KB sector to store partition information and bootloader. It allows us to create up to 128 partitions. Since it supports too many partitions by default, it does not use the concept of primary, logical, and extended partitions. It also saves a copy of the partition information before the end of the disk for redundancy.
These features are not available in MBR. MBR stores partition information and the bootloader program in the first sector of the hard disk. It uses a 512 bytes sector. Due to this, it can store information about a maximum of 14 partitions and 2 TB of disk space.
To address this issue, GPT uses a sector of 4KB. 4KB sector space allows GPT to store information about up to 128 partitions, and each partition can have a maximum of 18 exabytes of space.
The MBR is non-redundant. It stores information only in a single place. It means if the first sector corrupts, the disk becomes useless. To solve this issue, GPT stores a copy of the partition information before the end of the disk for redundancy.
MBR and GPT on the same disk
MBR uses the first sector of the hard disk to save the partition information. GPT saves partition information in a .efi file on the hard disk. Hence, you can use both MBR and GPT on the same disk. There is only one restriction for this setup. Systems that use the UEFI framework need the boot partition on the GPT disk. Other disks can be either MBR or GPT.
Key points:-
- GPT stands for Globally Unique Identifiers Partition Table.
- GPT supports up to 128 partitions. Each partition can have a maximum of 18 exabytes of space.
- GPT uses a sector of 4KB to save partition information.
- GPT supports redundancy.
- GPT was developed to remove the limitations of MBR and fulfill the requirements of modern systems.
- If your hard disk is less than 2TB, you can use both MBR and GPT. But if your hard disk is larger than 2TB, you can use only GPT.
- You can use both MBR and GPT on the same disk.
