| <<< Booting the OS from the MBR | Index | Sectors beyond MBR >>> |
The boot code in a DOS disk exists in the first 446 bytes of the first 512 byte sector, which is the MBR.
The end of the sector contains the partition table.
Boot sector viruses insert themselves into the first 446 bytes of the MBR so that they are executed every time the computer is booted.
The master boot record is read from the first sector of the disk, and the four partition table entries are identified and processed.
| <<< Booting the OS from the MBR | Index | Sectors beyond MBR >>> |