GRUB: The Grand Unified Bootloader
Like LILO, the GRUB boot loader can load other operating systems in addition to Linux. GRUB was written by Erich Boleyn to boot operating systems on PC-based hardware, and is now developed and maintained by the GNU project. GRUB was intended to boot operating systems that conform to the Multiboot Specification, which was designed to create one booting method that would work on any conforming PC-based operating system. In addition to multiboot-conforming systems, GRUB can boot directly to Linux, FreeBSD, OpenBSD, and NetBSD. It can also boot other operating systems such as Microsoft Windows indirectly, through the use of a chainloader . The chainloader loads an intermediate file, and that file loads the operating system’s boot loader.
GRUB provides a graphical menu interface. It also provides a command interface that is accessible both while the system is booting (the native command environment) and from the command line once Linux is running.
While LILO works perfectly well, especially if you usually boot the default image, GRUB has some advantages. The graphical menu interface shows you exactly what your choices are for booting so you don’t have to remember them. It also lets you easily edit an entry on the fly, or drop down into the command interface. In addition, if you are using the menu interface and something goes wrong, GRUB automatically puts you into the command interface so you can attempt to recover and boot manually. Another advantage ...