Normally we’d use dd to clean wipe a hard drive as follows after opening a terminal window for a hard disk or USB drive accessible as /dev/sdb :
$ sudo dd if=/dev/urandom of=/dev/sdb status=progress <enter>
Another command to do a secure wipe of /dev/sdb is scrub that can be used as follows:
$ sudo scrub -p dod /dev/sdb <enter>
Note that the above commands completely wipe data and if run by accident will cause data loss. Exercise due caution when using them.