If you don't know what a leaked database search engine is, it's simply a website that compiles large amounts of leaked database data and allows you to perform cash searches in uncensored results. For example, if your friend's information was leaked because they signed up on an insecure site, or if the site was hacked (even large sites can be hacked, and have been, and large amounts of information has been leaked from these sites), then their credentials will likely appear in the search engine. All you need is their email address; you can even search email domains like your school domain if you want. Basically, if your friend uses the internet a bit and is over ~17 years old, their information will likely show up.
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