What is GPT Disk and MBR Disk

When you are initializing a new hard drive with built-in Disk Manager in windows, a window pops up and asks you to choose between MBR (master boot record) and GPT (GUID partition table) disk.  a brand new hard disk must be initialized before you can partition it for data storage. So when you install a new hard drive to the computer, it will first initialize the disk and ask you to choose between MBR and GPT partition style. Typically, most people would straightly click next step without knowing any of the advantages or disadvantages among MBR and GPT. So today we I tell you the difference between GPT Disk and MBR Disk

MBR Disk

The MBR, short for Master Boot Record, is an old and commonly-used disk layout. It was introduced with IBM PC DOS 2.0 in 1983. This sector contains a boot loader for the installed operating system and information about the drive’s loTgical partitions. The boot loader is a small bit of code that generally loads the larger boot loader from another partition on a drive. If you have Windows installed, the initial bits of the Windows boot loader reside here—that’s why you may have to repair your MBR if it’s overwritten and Windows won’t start. If you have Linux installed, the GRUB boot loader will typically be located in the MBR.

Working of MBR Disk

          MBR only works with disks up to 2 TB in size. MBR also only supports up to four primary partitions—if you want more, you have to make one of your primary partitions an “extended partition” and create logical partitions inside it. Now there are two type of partitions.
1. Primary partitions
2. Logical partitions

In MBR there are only four primary partitions if we need more partitions then we have to convert fourth primary partion to a logical partion then we make small logical partitions as many we need.

You can understand with diagram there are a partition table and there are four partition table entries and there are three primary partitions and the fourth partion is converted into a logical partion and there are extended partitions in logical drive. So that is the working of MBR Disk.

Working of GPT Disk

GPT means GUID (globally unique identifier) Partition Table. It’s a new standard that is replacing MBR. This MBR has no limits. Drives can be much, much larger. It will depend on the operating system and its file systems. GPT allows for a nearly unlimited amount of partitions, and the limit here will be your operating system Windows allows up to 128 partitions on a GPT drive, and you don’t have to create an extended partition.

As you can see there are 128 GUID Partition entries are available. So there are 128 primary partitions are possible.

How to check if your hard disk is MBR or GPT?

STEP 1. Press windows+R to open run dialog box, write diskmgmt.msc  into the box and click ok.

STEP 2. Select the disk you want to check. Right-click it and select "Properties".

Step 3: Select the Volumes tab. In Partition style line, you'll know whether your disk is MBR or GPT.

As you can see my disk is MBR and you can see you own disk.