I ran a "full format operation" (unchecked "quick format") on my disk. Does this remove data in a secure way? I have read answers for related questions and looked on Wikipedia, but am still unclear how it works.
I feel like it doesn't fill every byte with zeroes, but instead it just checks for bad disk sectors and reallocates them. I'm mainly looking at security aspects for this question. It looks my disk is insecure for data restore.