Originally Posted by kaushalsingh
plz. suggest why the options like "change cylinder no. , change sectors etc. " are given in expert command .
One possibility is that the cylinder, sector etc. changing feature of fdisk was once useful and has not been removed in case fdisk is used on old HDDs. Some legacy features are inevitable in utilities that are nearly 40 years old.
From the fdisk man page
Specify the number of cylinders of the disk. I have no idea why anybody would want to do so.