http://www.digipedia.pl/man/doc/view/sfill.1/

Though I strees read the instructions throughly, if you are looking to delete
all data on harddrives in your system then an easy option is to download and run
http://www.dban.org/

Try: sudo shred -n2 -v /dev/sdx where sdx is your hard drive or partition
(will be followed by partition number such as sda1); n2 is the number of
shreds. More shreds is better but takes longer. You can also try: sudo dd
if=/dev/zero of=/dev/sdx (with sdx being same as above). In this case it
restores the drive to zero or factory state. I have never tried this as
shred works for me.

I have shred in Nautilus but it doesnt ask to get you to confirm to destroy the
data which i find very dangerous, I wonder, can we edit it to run in a terminal
and have the terminal produce a "type yes to confirm" message?

So, it is actually possible to erase the hard drive without crossing it!....well thats a good news. When I will use the shred command, it will format the drive completely, wont it?

It does not format. It writes and rewrites over the data so that it cannot
be restored. This is why it takes time.

As of the last time i checked, shreddoes not support an interactive mode.

Have used Wipe it - Works well,but slow,

Maybe shred doesnt, but, can we not put a command in before the shred to produce
a confirmation message in the terminal?