In fact, in the early hard disk partitions, there is no concept of primary partition, extended partition and logical partition. The type of each partition is now called the primary partition. Since the hard disk only reserves 64 bytes of storage space for the partition table, and the parameters of each partition occupies 16 bytes, the master boot sector can only store data of 4 partitions in total. In other words, a physical hard disk can only be divided into 4 primary partition disks. In specific applications, four primary partition disks often cannot meet actual needs. In order to create more disk partitions for use by the operating system, extended partitions and logical partitions are introduced, and the original partition type is called the primary partition. 1. A hard disk has at least one primary partition and a maximum of 4, but the extended partition does not need to be, and a maximum of one. And the total number of primary partition + extended partition cannot exceed 4. There can be several logical partitions. 2. After the main partition is divided, the remaining part can be divided into extended partitions. Generally, all the remaining parts are divided into extended partitions, or not fully divided, and the remaining part is wasted. 3. The extended partition cannot be used directly, and must be divided into several logical partitions. All logical partitions are part of extended partitions. The capacity of the hard disk = the capacity of the main partition + the capacity of the extended partition; The capacity of the extended partition = the sum of the capacities of each logical partition. 4. A logical disk composed of a primary partition and a logical partition is called a drive (Drive) or a volume (Volume). 5. The difference between the system partition and the boot partition: the activated primary partition will become the “system partition”. The system partition contains hardware-related files and the Boot folder. Through this folder, the computer can obtain the location where Windows is started. By default, if you install Windows 7 from scratch on an unpartitioned hard drive (as opposed to upgrading from the previous version of Windows), a separate system partition will be created. The partition size is 100 MB. The boot partition is the partition containing the Windows operating system files. For example, if there is a multi-boot computer that contains Windows Vista on one volume and Windows 7 on another volume, then these two volumes are considered to be boot partitions. The system partition and the boot partition are the names of the partitions (or volumes) on the hard disk, and Windows will use the hard disk when it starts. These two terms are easy to confuse, because the system partition actually contains the files used to start Windows 7, while the boot partition contains system files. 6. In DOS/Windows, inactive primary partitions and extended partitions cannot be seen, but Windows 2000/Vista and other NT kernel versions can view all partitions in Disk Management.