There are times where you have to change one HDD and you whant to give it away, selling or giving for free it's not

the problem, the problem is the data inside, with a new format process anyone with a file recovery software can

recover almost all the content.

Another scenario could be your thumbdrive or SD card that doesnt perform well because is slow or sometimes gives you

input / output errors.

dd 

On Linux you have the dd command that suits perfectly, so we are gonna write a string of zeroes on the entire volume

but pay attention, find the correct volume with fdisk -l because you don't want to destroy useful data of the wrong HDD

or even worse your system!!

Insert your drive, switch to admin with su or sudo and type fdisk -l, as you can see my older SD card is device /dev/sdc

fdisk

Time to erase everything with dd if=/dev/zero of=/dev/sdc, during dd you'll dont see an advancing reference, wait untill stops. 

dd

And here we go, now no one can find data from our old HDD / flash card or thumbdrive could be fixed (if the problem wasn't

damaged old clusters).  The error you see is probably because i used a wrong block size, anyway the volume is EMPTY.

Click here to partition / format a filesystem for MP3 car players.