On DOS systems,there are ordinary boot-sector viruses,which infect only the DOS boot sector,and MBR viruses which infect the Master Boot Record on fixed disks and the DOS Bootsector on diskettes.

• 在DOS系统中，常见的引导扇区病毒和主引导记录病毒，前者只感染DOS引导扇区，后者感染硬盘的主引导记录和软盘的DOS引导扇区。