How do you delete files on your Mac? If you drag and drop them to the Trash can and select Empty Trash from the Finder menu, well, guess what? Nothing got deleted. When files are created on your Mac each one is given a little flag– visible or not. When files are deleted they remain but are not visible. OS X, though, is free to use the space taken up by those files, but it may be some time before that happens.
If you have incriminating files that need true deletion there are a couple of ways. Use the built-in Secure Empty Trash selection in the Finder’s menu. That slices and dices and Juliennes the files many times which makes them far more difficult for hackers and spooks to retrieve.
Or, use Shred, a Mac utility that also securely erases files on your Mac, by overwriting the deleted data up to 35 times, and changing the name and date of both deleted and erased files and folders to random values. The way Shred works is simple, too. Drag and drop folders and files you want to terminate with extreme prejudice and click the Shred button.
Shred starts to work on files by searching through the folders of files you want to delete. Any files inside will be shredded; overwritten. Names and dates will be changed, and the folder deleted.
What you end up with is more like digital spaghetti than a file, and splicing anything of value back together again is nearly, mostly, probably impossible. Yes, of course it can be done on NCIS, but we’re talking reality here.
Shred doesn’t really cost much considering the added level of security it places upon incriminating files on your Mac, but even the built-in way to Securely Empty Trash is better than simply emptying the Mac’s trash.