Very good question on what each one is when your backing up. Not understanding this carefully can cost you on loosing your hard drive information, should you current drive fail one day.
In non computer terms:
In easier terms an Image is an exact copy of your hard drive when a clone is just a copy of the data of information on that computer.
If you just need the data on your computer then a Clone is what you need. If you want to backup all of your computer software, etc then it's a good idea to make an Image of that hard drive.
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