What Is Hard Disk Partitioning? Everything You Need to Know in 2024

A hard drive partition refers to sections of a hard drive's storage space. Most operating systems allow users to divide a hard drive into multiple partitions, effectively turning one physical hard drive into several smaller logical drives.

Reasons for Using Hard Disk Partitioning

It is common for users to divide a hard disk into multiple partitions, so that data can be organized more efficiently. On a computer running Microsoft Windows, the operating system and applications are typically stored on one partition of the hard disk, and user data on another. In the event of problems with Windows, the operating-system partition can be reformatted and reinstalled without affecting the data partition.

Users might choose to partition a hard drive into several partitions because smaller partitions often have a smaller cluster size. The cluster size is the smallest unit of data that a partition can store. A large partition may have a 16KB cluster size, meaning a file with only one character would take up 16KB of space on the disk. On a smaller partition, that same file might only take up 4KB. This can be useful if you need to store many small files.

If the hard disk is larger than the maximum partition size supported by the operating system, the user might need to break it up into multiple partitions.

Read More: Repartition Hard Drive

Create a hard drive partition

Most operating systems use the fdisk command to create disk partitions. Many also have graphical tools that do the same thing, such as the GParted partition manager.

Hard Disk Partitioning and File Systems

You don't actually store data within partitions on the disk.

You store file systems on your disk partitions, and data within those file systems.

Some operating systems blur the distinction between a partition and a file system.

Partition Table

Partition information is stored in the reserved area at the beginning of the hard drive, in the Partition Table.

Extended partition

A traditional partition table can only hold information for four partitions, which means that a hard drive could have no more than four partitions.

To overcome this limitation, extended partitions were created.

An extended partition is used to store information about other partitions. By using an extended partition, you can have more than four partitions on a hard drive.

These four primary partitions are often called main partitions.

Partitions formatted as extended are often called logical partitions.

Partition Type

When a partition is created, a special byte pattern is written to identify the partition type.

Because a disk may be shared by multiple operating systems, there is a tendency for these values to have consistent meanings.

The following table lists some of the partition types in use.