--FS--R-- Boot sector, loads /system/boot.sys, and drivers required to boot root fs, jumps to boot.sys --OS--R-- /system/boot.sys, can be loaded anywhere, switches to protected mode, uses drivers to load kernel.sys and complete root fs drivers into memory --OS--P-- /system/kernel.sys, starts multi-tasking, starts all drivers, then starts /system/init, kernel.sys is multi-boot complient