SYSTEM PARTITION AND BOOT PARTITION In Microsoft Windows, the system partition and boot partition refer to: The system partition is a disk partition that contains the boot sector and files such as NTLDR that are needed for booting Windows XP and earlier. (Windows Vista and Windows Server 2008 use a newer boot loader called bootmgr that replaces NTLDR and is configured using BCDEdit.exe). The boot partition is the disk partition that contains the Windows operating system files and its support files, but not any files responsible for booting. The system partition can be different from the boot partition, although they are often on the same partition (drive C:). Windows setup places the initial system partition based on motherboard BIOS settings. Bitlocker requires a separate, unencrypted system partition for booting. The master boot record is located at physical sector 0, just before the partition table, and is therefore not contained inside any of the logical partitions or volumes.  Other operating systems It is interesting to note that in operating systems other than Windows and DOS the definitions of boot partition and system partition are just the opposite: the boot partition contains the boot files and the system partitions hold the operating system files. 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/ while operating system files are mounted at / (the root directory); these may or may not be separate partitions, but they are mounted in the same hierarchy.