There are 2 parts to LILO
  1. The installer
  2. The bootstrap
Installed in the master boot record (MBR) or
as a secondary bootstrap manager in the boot sector of a partition and another bootstrap is installed in the MBR to load LILO.

Uses BIOS to access disks (not some other driver)

As LILO boots it displays:

  1. L, first stage boot loader has been loaded and started
  2. LI, second stage boot loader has been loaded
  3. LIL, Second stage started ( if LILO stops here, it can't load the descriptor table from the map file. a media failure or by bad disk parameters in the BIOS.
    LIL? second stage has been loaded at an incorrect address, bad disk parameters in the BIOS.
    LIL- descriptor table is corrupt, bad disk parameters in the BIOS
  4. LILO All is loaded

Files

When installing:
/etc/lilo.conf

/boot/boot.MMmm backup of original boot sectors (MM=major,mm=minor Device Numbers) needed to un-install and restore to previous bootstrap program.

NOTICE: running multiple times will NOT clobber the original bootstap!

To restore previous bootstrap:
dd if=/boot/boot.MMmm of=/dev/hda bs=446 count=1
-or-
fdisk
-or-
MicroSoft fdisk /mbr

-MWrite MasterBoot Record

Example

large-memory
lba32
boot=/dev/hda
install=menu
map=/boot/map
prompt
 
default=Linux
image=/boot/vmlinuz-2.6.26

label="Linux"
root=/dev/hda2

label = windoz
table = /dev/hda1

append=""
read-only
optional
 

see Wikipedia

GRUB is successor.