x86PC - Master Boot Record

Master Boot Record (MBR)

Some notes on MBR used in classic/legacy BIOS-based system.

first sector of a partitioned storage
- also known as disk boot sector
- contains a partition table (info on how the disk is partitioned)
classic MBR
- 446 bytes executable code
- 64 bytes partition entries (4 primary partitions)
- 2 bytes boot signature (0x55 0xAA)
modern MBR
- 218 bytes executable code
- 2 bytes (always 0x00?)
- 4 bytes disk timestamp
- 216 bytes executable code
- 4 bytes disk signature
- 2 bytes (always 0x00?)
- 64 bytes partition entries (4 primary partitionss)
- 2 bytes boot signature (0x55 0xAA)
primary job of embedded code is to boot/load Volume Boot Record (VBR)
superseeded by GUID partition table (GPT) - Read more @ wikipedia

first sector of a partition on a partitioned storage
- also known as partition boot sector