Data Storage - Boot sector (Sector 1)

Card Puncher Data Processing

Data Storage - Boot sector (Sector 1)


The boot sector, located at sector 1 of each volume, is a critical disk structure for starting your computer. It contains executable code and data required by the code, including information that the file system uses to access the volume.

Windows Disk

The boot sector is created when you format a volume.

At the end of the boot sector is a two-byte structure called a signature word or end of sector marker, which is always set to 0x55AA.

On computers running Windows 2000, the boot sector on the active partition loads into memory and starts Ntldr (NT Loader), which loads the operating system.

The Windows 2000 boot sector consists of the following elements:

  • An x 86-based CPU jump instruction.
  • The original equipment manufacturer identification (OEM ID).
  • The BIOS parameter block (BPB) , a data structure.
  • The extended BPB .
  • The executable boot code (or bootstrap code) that starts the operating system.

Discover More
Windows Disk
Data Storage - Boot Sector Startup Processes

Two sectors are critical to start a computer on Windows: the master boot record (MBR), the first sector of a hard disk and the boot sector, which resides at sector 1 of each volume. These sectors...
Windows Disk
Data Storage - Extended Boot Record

An extended boot record (EBR), or extended partition boot record (EPBR), is a descriptor for a logical partition under the common DOS disk drive partitioning system. An EBR consists of: an extended...
Disk - Sector (Physical block)

A sector is the block (minimal persistent unit) on a disk at the physical level. It is not possible to modify any part of the disk smaller than a sector. To change a part of the disk smaller than a sector,...
Windows Disk
Drive - The Master Boot Record (MBR)

A master boot record (MBR), or partition sector, is the first 512-byte sector (Logical_block_addressingLBA/absolute sector 0) of a partitioned data storage device such as a hard disk. The master boot...

Share this page:
Follow us:
Task Runner