Hi, I ran a quick search but couldn't find what I was looking for.

If I were to collect desktops, laptops, or bare hard drives, what exactly is a Certificate of Data Destruction - I may be lacking the proper terms here.

I see others offering to provide some kind of certificate staring the hard drives data has been irreversibly destroyed or erased. What does this mean? Is there some official license or certification I need in order to make this claim? Or does it just need to meet a certain specification?