GRUB: A common man with zilch knowledge of Linux would think we are talking about food, yet every Linux user knows that GRUB is the GNU Grand Unified Bootloader.

GRUB has earned the name of being one of the greatest loader for booting Linux and practically any other OS.

It is especially useful for multi-boot, partitioned system since GRUB offers high flexibility and convenience for different startup options.

The GRUB kernel recognises file systems and loads boot images, and also it provides both menu-driven and command-line interfaces to perform these functions.
It has a very flexible and powerful command-line interface. Moreover it has features like command history and completion which is similar to bash shell.

What if you're using Windows XP in a dual boot system and disaster strikes and you have to reinstall and you don’t have a Linux live cd ?

Then how do you run GRUB ?

The solution is somewhat simple simple: all you have to do is put Linux on the Windows XP boot list (boot.ini).

First of all you have to create an image from the master sector from a HDD that has GRUB installed.

Open terminal and type:
sudo dd if=/dev/sda1 of=bootsect.lnx size=512 count=1

You might have to change /dev/sda1 depending on your HD.

Executing this command creates a bootsect.lnx file.
Transfer it to c:\ on Windows.

After that you will have to edit the boot.ini on Windows.

There are two ways to edit boot.ini on Windows.

One way is to edit the c:\boot.ini directly (it may be hidden and read-only) or else right click on “My Computer”, and then navigate through “Preferences”, and then “Advanced” tab, and click the button to edit boot preferences.

That should get boot.ini open in notepad.

Paste the following line at the end of the file:
c:\bootsect.lnx="Linux Boot"

Save, close and reboot.

Now your Windows asks you if you want to start Windows or Linux.