Compare SuperDuper and CarbonCopyCloner

        It's important to backup what you've got on your computer.  But what's the best way?  John Carter compares two programs.  "What’s the difference between SuperDuper! (SD) and CarbonCopyCloner (CCC)?
        "In a word, money. But there is more.
        "Either SD or CCC are okay for cloning the entire internal hard drive to an external hard drive for saving a full backup for emergencies. Such a clone can be booted from, and you can restore your internal drive from that clone up to the point that the clone was created. I suspect that SD is winning out over CCC for cloning. However, you can’t use all the features of SD without purchasing it.
        "A major functional difference between SD and CCC is that SD always does a full erase of the target disk and CCC never does a full erase of the target disk. Making a clone with CCC requires that you first use Disk Utility to format the target drive. After the clone is created, you really should be using CCC to keep your clone updated if you’re not using Time Machine.
        "Another difference is that SD will clone either the entire source or just  /Users on the source. With CCC you can select the files and folders you want to backup, and this is most helpful for performing incremental backups.
     (Click on each illustration to enlarge.)

 "Setting up the options for either one doesn’t give you any warm feeling that you will have a bootable copy when it’s done, but my recent experience with SD is that after you click on Copy it gives you a laundry list of things it will do and it includes a notice that it will set the target disk to be bootable. CCC just tells you its done. If you started with a properly formatted drive (one partition, Mac OS journaled), you won’t have any problems booting from it if all the system files are on the drive.
        "Be aware that booting from a USB drive and launching applications from same is painfully slow."