Hard disk drive partitioning

Disk partitioning or disk slicing is the creation of one or more regions on a hard disk or other secondary storage, so that an operating system can manage information in each region separately. Partitioning is typically the first step of preparing a newly manufactured disk, before any files or directories have been created. The disk stores the information about the partitions' locations and sizes in an area known as the partition table that the operating system reads before any other part of the disk. Each partition then appears in the operating system as a distinct "logical" disk that uses part of the actual disk. System administrators use a program called a partition editor to create, resize, delete, and manipulate the partitions.When a hard drive is installed in a computer, it must be partitioned before you can format and use it. Partitioning a drive is when you divide the total storage of a drive into different pieces. These pieces are called partitions. Once a partition is created, it can then be formatted so that it can be used on a computer.

Creating more than one partition has the following advantages:

Creating more than one partition has the following disadvantages, as compared to having a single partition spanning the same disk area:

This section describes the master boot record (MBR) partitioning scheme, as used historically in DOS, Microsoft Windows and Linux (among others) on PC-compatible computer systems. As of the mid-2010s, most new computers use the GUID Partition Table (GPT) partitioning scheme instead. For examples of other partitioning schemes, see the general article on partition tables.

The total data storage space of a PC HDD on which MBR partitioning is implemented can contain at most four primary partitions, or alternatively three primary partitions and an extended partition. The Partition Table, located in the master boot record, contains 16-byte entries, each of which describes a partition.

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