Advantages of GRUB

1) Grub has got several added advantages, compared to previous boot loaders, and also many "Proprietary boot loader's".

2) Grub can be used to load, almost all operating system's available, with the help of a function called chain-loading.

3) Grub does not require the exact physical location of the operating system kernel in the

hard disk. It just requires the hard disk number(like the first hard disk,second hard disk),

and the partition number, along with the file name of the kernel. Because, 

4) GRUB understands the format in which kernel is made.

You can modify, the booting options, like kernel parameter's and its location while booting, through GRUB command line.

Note: Taken from net

Regards

Gurudatta N.R