Uninstalling Ubuntu 17.10

[fatharraxman]

Dear all,
I have an Ubuntu 17.10 in my computer I need to remove it completely and leave no track of it in this computer as it does not belong to me anymore, this computer is not attached to internet so I can not install OS-uninstaller. Could someone help me do this please? using terminal , I also can not recall my root passwd for maintenance in case someone advice me to do that?

Is this possible?

Many thanks in advance

[howefield]

It might help to know whether or not Ubuntu is the sole operating system on the machine, if it the sole OS, using gparted from a Live media would probably be easiest.

[fatharraxman]

Thank you, and yes it is the sole system there.

[Impavidus]

If you want to remove Ubuntu without a trace, which is indeed a good idea if you transfer the computer to someone else, you have to wipe the hard drive. Use a live disk to boot the computer. It doesn't matter what flavour or distro or version, as long as it boots it's fine. Then wipe the drive. See for example http://how-to.wikia.com/wiki/How_to_...clean_in_Linux