Boot Loader

The boot loader is a small program that runs before the operating system is loaded that tells the machine where, on the disks, that valid operating systems are installed. Windows (tm) also has a boot loader, but you don't hear much out of it, and it is somewhat less functional than most bootloaders.

The most common boot loaders on Linux are GRUB (the GRand Unified Bootloader) and LILO (the LInux LOader).

• LILO: The earlier bootloader for Linux. It has been proven over many years of usage. Most sysadmins will know LILO very well.
• GRUB: Much newer. More powerful, interactive command line. No need to "rebuild" the bootloader upon install of a new OS. Well documented.