Yes, if you use Disk Utility or CarbonCopyCloner (version 3.4.7 is still free and available for download here and works with Mac OS X 10.6 Snow Leopard, Mac OS X 10.7 Lion and OS X 10.8 Mountain Lion) or SuperDuper! to clone your drive to another and have not checked off some folders or files, thus have set the application to do a complete clone.