
If you are using SSD and want to securely wipe it (so no one can recover data), then you are in a trouble since it isn’t as easy as with HDD thou faster.

If you are using SSD and want to securely wipe it (so no one can recover data), then you are in a trouble since it isn’t as easy as with HDD thou faster.
shred -v -n 3 ./file
Thou might not be secure if your filesystem use COW (copy-on-write) (like btrfs,zfs), make shadow copies (windows, ntfs), uses RAID.
shred -v -n 3 /dev/HDD
# Or if you are paranoid - slower
shred -v -n 7 /dev/HDD
Long. Expect waiting a day or two.