"System partition" redirects here. Not to be confused with
EFI system partition.
"Boot partition" redirects here. Not to be confused with
BIOS boot partition.
The system partition and the boot partition (also known as the system volume and the boot volume) are computing terms for
disk partitions of a
hard disk drive or
solid-state drive that must exist and be properly configured for a computer to operate. There are two different definitions for these terms: the common definition and the
Microsoft definition.
Common definition
In context of every operating system, except those developed by
Microsoft, the system partition and the boot partition are defined as follows:
The boot partition is a
primary partition that contains the
boot loader, a piece of software responsible for
booting the
operating system. For example, in the standard
Linux directory layout (
Filesystem Hierarchy Standard), boot files (such as the
kernel,
initrd, and boot loader
GRUB) are mounted at /boot/.[1] Despite Microsoft's radically different definition (see below), System Information, a utility app included in
Windows NT family of operating systems, refers to it as "boot device".[2][3]
The system partition is the disk partition that contains the operating system folder, known as the system root. By default, in Linux, operating system files are mounted at / (the
root directory).
In Linux, a single partition can be both a boot and a system partition if both /boot/ and the root directory are in the same partition.
Microsoft definition
Since
Windows NT 3.1 (the first version of Windows NT),[4] Microsoft has defined the terms as follows:
The system partition (or system volume)[5] is a primary partition that contains the boot loader, a piece of software responsible for booting the operating system.[6]: 1087 This partition holds the
boot sector and is marked active.[7]: 970
The boot partition (or boot volume)[5] is the disk partition that contains the operating system folder, known as the system root or %systemroot% in
Windows NT.[6]: 174
Before
Windows 7, the system and boot partitions were, by default, the same and were given the "C:"
drive letter.[7]: 971 Since Windows 7, however,
Windows Setup creates, by default, a separate system partition that is not given an identifier and therefore is hidden. The boot partition is still given "C:" as its identifier. This configuration is suitable for running
BitLocker, which requires a separate unencrypted system partition for booting. As of
Windows 11, this nomenclature is still used by the "Disk Management" utility.
^Petersen, Richard (2009). "Chapter 21: Basic System Administration". Ubuntu The Complete Reference. New York: McGraw-Hill. p. 473.
ISBN978-0-07-164368-9.
^Andrews, Jean; Chellis, James (13 August 2012). A+ Guide to Software (6th ed.). Cengage Learning. p. 21.
ISBN9781285414980.
^Donald, Lisa (2008). MCSA / MCSE: Windows Server 2003 Environment Management and Maintenance Study Guide: Exam 70-290 (2nd ed.). John Wiley & Sons. pp. 116–117.
ISBN9780470327616.