I'm running El Capitan 10.11.6 on a Mac Pro (early 2009). In Finder I can right-click on a file and one of the options is 'Delete Permanently'. What exactly does that do to the file? I notice that my Macbook Pro with Sierra 10.12.6 does not have that option. Does it replace the 'Secure Empty Trash' option that was removed from El Capitan? Thanks!