When you delete a file on your MAc, OS X only removes the index entry for the file, which tells the system the file’s contents are free to be overwritten; however, the data still technically remains and may be recovered using specialty software. To prevent this, you can use a secure-erase option that overwrites files you delete, but while this has been a built-in option in OS X, Apple has removed this in at least the initial release of El Capitan. Continue reading →