what is Master boot record and LILO ?

Master boot record and LILO

What is the master boot record (MBR) and why does LILO erase the old boot loader? Every hard drive has a
top space called the MBR where the BIOS will try to load an operating system. Every system has its own
loader. DOS has DOS-MBR, Windows NT has the NTLDR and Linux has LILO.
When you install LILO, you can install it in the MBR or in a boot record for the Linux partition. If you want
to keep your current boot loader, you can select the Linux partition, and make sure it is the active partition in
fdisk. This way you will be able to boot to LILO, and then boot the old loader from the MBR.
If you plan on only using Linux on your system, you can tell LILO to boot right into Linux and not display a
"boot:" prompt, and you can install it in the MBR.

Master boot record (MBR) is a type of boot sector popularized by the IBM Personal Computer.It consists of a sequence of 512 bytes located at the first sector of a data storage device such as a hard disk. MBRs are usually placed on storage devices intended for use with IBM PC-compatible systems.

The MBR may be used for one or more of the following:

• Holding a partition table which describes the partitions of a storage device. In this context the boot sector may also be known as a partition sector.
• Bootstrapping an operating system. The BIOS built into a PC-compatible computer loads the MBR from the storage device and passes execution to machine code instructions at the beginning of the MBR.
• Uniquely identifying individual disk media, with a 32-bit disk signature, even though it may never be used by the operating system.