EMZETT.Partitions
In short: A partition is a delimited area of a disk that is treated like a drive of its own. Each partition holds a file system.
In more detail: A hard drive or SSD is divided into sections by a partition table (MBR or GPT). The operating system sees each section as a separate drive (for example C: and D:).
In Depth
Why partition?
- Separate operating system and data. Data survives a reinstall.
- Several operating systems on one disk (dual boot).
- Special areas: boot partition, recovery, swap.
- Different file systems or encryption.
Typical partitions of a Windows 11 computer (GPT):
| Partition | Size | Purpose |
|---|---|---|
| EFI system partition (ESP) | 100 – 260 MB | Bootloader and startup files |
| Microsoft reserved (MSR) | 16 MB | Management, not visible |
| Windows (C:) | the main part | Operating system and programs |
| Recovery | 500 – 1000 MB | Windows recovery environment (WinRE) |
File systems: NTFS (Windows), FAT32/exFAT (USB, EFI), ext4 (Linux), APFS (macOS).
Tools: Windows Disk Management, diskpart, Linux fdisk, gdisk, parted, GParted.
Kinds with MBR: Primary (max. 4), extended (container for any number of logical drives), active (the one booted from).
- Growing/shrinking: Usually possible without data loss, but make a backup first.
- Partition ≠ drive ≠ disk: A disk contains partitions. A drive is the letter under which a partition becomes visible.
- Dangers: Formatting or deleting the wrong partition destroys data.
See also: GPT (GUID Partition Table), MBR (Master Boot Record), EFI system partition and system partition