Installing a boot loader

“In order to be able to boot your Red Hat Linux system, you usually need to install a boot loader. In Red Hat Linux 7.2 you have two options, GRUB or
LILO (the LInux LOader). You may install the boot loader in one of two places:

The master boot record (MBR)
The recommended place to install a boot loader, unless the MBR already starts another operating system loader, such as System Commander or
OS/2’s Boot Manager. The MBR is a special area on your hard drive that is automatically loaded by your computer’s BIOS, and is the earliest
point at which the boot loader can take control of the boot process. If you install it in the MBR, when your machine boots, GRUB (or LILO) will
present a boot prompt. You can then boot Red Hat Linux or any other operating system that you have configured the boot loader to boot.

The first sector of your root partition
Recommended if you are already using another boot loader on your system (such as OS/2’s Boot Manager). In this case, your other boot loader
will take control first. You can then configure that boot loader to start GRUB (or LILO), which will then boot Red Hat Linux.”