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Today, I would like to share with you the relevant knowledge of what the form of Windows disk partition is, the content is detailed, and the logic is clear. I believe most people still know too much about this knowledge, so share this article for your reference. I hope you can get something after reading this article.

There are two forms of disk partition: 1, MBR (Master Boot record), which is a special boot sector that exists at the beginning of the disk drive; 2. GPT (GUID Partition Table), which is a disk organization that uses UEFI to boot.

The operating environment of this tutorial: windows7 system, Dell G3 computer.

There are two forms of disk partitioning, MBR and GPT.

When you buy a new hard drive and set up a partition, the system will ask you if you want to use MBR partition or GPT partition (some hard drives are given to you by default when they ship from the factory). MBR is the former form of partition, while GPT is a new form of partition, which is now gradually replacing the form of MBR partition.

MBR partition

MBR, which means "master boot record", was proposed by IBM company earlier. It is a special boot sector that exists at the beginning of the disk drive. This sector contains information about the installed operating system and uses a small piece of code to start the system. If you install Windows, its startup information is in this code-if the MBR information is corrupted or mistakenly deleted, you will not be able to start Windows properly, then you need to find a boot repair software tool to fix it. In Linux systems, MBR is usually the GRUB loader. MBR . When a computer starts, it starts the BIOS system that comes with the motherboard, and bios loads MBR,MBR and then starts Windows. This is the startup process of mbr.

GPT partition

GPT means GUID Partition Table, that is, the globally unique identification disk partition table. It is another more advanced and novel way of disk organization, a way of disk organization started using UEFI. At first, it was for better compatibility, but later it was widely used because of its larger memory support (mbr partitions support up to 2T disks) and more compatibility, especially for Apple's MAC system, which uses all gpt partitions. Gtp no longer has the concept of partition, and all CDEF disks are stored in a piece of information. It can be simply understood as a more advanced but not widely used technology.

GPT brings a lot of new features, but MBR still has the best compatibility. GPT is not a new standard dedicated to Windows-Mac OS XMagi Linux, and other operating systems also use GPT. You must partition the new disk before using it. MBR (Master Boot Record) and GPT (GUID Partition Table) are two different ways to store partition information on disk. This partition information contains where the partition starts so that the operating system knows which sector belongs to which partition and which partition is bootable. When creating partitions on disk, you have to choose between MBR and GPT. At present, there are and only these two forms of zoning.

Limitations of MBR

MBR, which means "master boot record", was first proposed in IBM PC DOS 2.0 in 1983. The "master boot record" is called because it is a special boot sector that exists at the beginning of the drive. This sector contains the partition information of the drive (64 bytes, fixed size, one partition is recorded with 16 bytes), the boot loader of the installed operating system (446 bytes) and the end flag of 2 bytes, so the size of this sector is 512 bytes. The so-called boot loader is a small piece of code used to load larger loaders on other partitions on the drive. If you have installed the Windows,Windows boot loader, the initial information is placed in this area-if the MBR information is overwritten and Windows cannot be started, you will need to use Windows's MBR repair feature to get it back to normal. If you install Linux, the GRUB loader is usually located in MBR. MBR supports maximum 2TB disks and cannot handle disks larger than 2TB capacity. MBR also supports up to 4 primary partitions-if you want more partitions, you need to create so-called "extended partitions" and create logical partitions in them. MBR has become the industry standard for disk partitioning and booting.

Advantages of GPT

GPT means GUID partition table. (GUID means globally unique identifier). This is a new standard that is gradually replacing MBR. It and UEFI complement each other-UEFI is used to replace the old BIOS, while GPT replaces the old MBR. It is called a "GUID partition table" because each partition on your drive has a globally unique identifier (globally unique identifier,GUID)-a randomly generated string that ensures that every GPT partition on the planet is assigned a completely unique identifier. This standard does not have the limitations of MBR. Disk drive capacity can be much larger than the operating system and file system can support. It also supports an almost unlimited number of partitions, limited only by the operating system-Windows supports up to 128GPT partitions, there is no concept of primary or extended partitions on GPT hard drives, and all partitions are called partitions. On MBR disks, partition and boot information are saved together. If this part of the data is overwritten or destroyed, things will be in trouble. In contrast, GPT keeps multiple copies of this information on the entire disk, so it is more robust and can recover the corrupted information. GPT also keeps cyclic redundancy check codes (CRC) for this information to ensure its integrity and correctness-if the data is corrupted, GPT will detect the corruption and recover it from elsewhere on disk. On the other hand, there is nothing MBR can do about these problems-it is only after the problem occurs that you will find that the computer cannot be started, or the disk partition is missing.

Compatibility of GPT

As you can see, in the first block of the GTP disk, there is also a tag similar to MBR (master boot record) called PMBR (protected MBR). The purpose of PMBR is that when using a partitioning tool that does not support GPT, the entire hard disk will appear as a protected partition to prevent the partition table and hard disk data from being corrupted. UEFI does not get partition information for GPT disks from PMBR. It has its own partition table, the GPT partition table.

Primary partition, extended partition, and logical partition

These nouns are only available in MBR because GPT supports an unlimited number of primary partitions. If you use the partition form of MBR, you will have at least one primary partition and no more than four primary partitions; if you want more partitions, you will have to create an extended partition, and then create multiple logical partitions in the extended partition. And the number of primary partitions + extended partitions is no more than four; extended partitions can be none or at most one; logical partitions can be none or multiple. Extended partitions cannot be enclosed between primary partitions.

The active primary partition is the boot partition of the hard disk, it is independent, it is also the first partition of the hard disk, and the normal partition is the C drive. After the main partition is divided, the rest can be divided into extended partitions, generally, the rest can be divided into extended partitions or not, and the rest will be wasted. But the extension cannot be used directly, it is used in the way of logical partition, so the extended partition can be divided into several logical partitions. Their relationship is an inclusive relationship, and all logical partitions are part of the extended partition. In linux, it is equivalent to a hda partition.

Capacity of hard disk = capacity of primary partition + capacity of extended partition

The capacity of the extended partition = the sum of the capacity of each logical partition

In the MBR partition table, there are up to 4 primary partitions or 3 primary partitions + 1 extended partition, which means that there can be only one extended partition, which can then be subdivided into multiple logical partitions.

In the Linux system, the hard disk partition is named sda1~sda4 or hda1~hda4 (sd for SCSI hard disk, hd for IDE hard disk, where a represents the hard disk number, if there are multiple hard drives, that is b, c, d * * 1 for the first partition, 2 for the second partition, and so on). In MBR hard disk, partition number 1mur4 is the primary partition (or extended partition), and logical partition number can only start from 5.

As shown in the figure, disks F, G and H in disk 1 are primary partitions, I+K+J is extended partitions, and I, K, J are logical partitions.

In windows, extended partitions are created by default only after you have created three primary partitions. If we want to create an extended partition directly, we can use the command

These are all the contents of the article "what is the form of Windows disk partitions?" Thank you for reading! I believe you will gain a lot after reading this article. The editor will update different knowledge for you every day. If you want to learn more knowledge, please pay attention to the industry information channel.

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