When you delete a file on your Mac, it goes to the trash. You empty the trash thinking that all traces of your private files are now completely erased from the Mac’s hard disk but that may not be the case.
Files deleted from the trash in this manner can still be recovered unless the sectors are overwritten by other files. There’s an easy way though. If you would like to permanently remove your deleted files, just remember to use the “secure” option while emptying the trash.
Here’s how. Click and hold the trash icon on your Mac desktop and it will display the “Empty Trash” option. Now press the Command button and the Empty Trash option will change to Secure Empty Trash. Select it and the trashed files will be gone forever.
The concept is similar in Windows though there’s no built-in option in Windows to permanently delete “deleted” files. You can however make use of the free SDelete utility to ensure that deleted files cannot be recovered again.
Emptying the trash, or the recycle bin in Windows, is not enough.