Microsoft moved a few things around in Windows 8. One of them is the system image backup feature, which lets you make a copy of your drive(s) so you can do a complete restore in case your system or hard drive dies.
If you search for "system image," no results come up. Search for "backup" and Windows 8 brings you to its new File History feature (which itself is pretty neat for saving copies of your files).
So where is the system image tool? You have to look for the "Windows 7 File Recovery" link in the lower left side of the File History page (or search for "file recovery"). It's not a very intuitive name, because it sounds like you'd be recovering Windows 7 files, but that's where the legacy backup tools are.
From there, you can set up a backup as you might have in Windows 7 and also find the "Create a system image" and "Create a system repair disc" options.
Choose "Create a system image" to clone your entire computer to another drive (or DVDs or a network location). Or, in the previous screen, choose to "Set up backup" and Windows will create both a system image and backup your data on a schedule. That's the best of both worlds: you'll have the option to recover individual files and folders (in case they've been accidentally deleted or overwritten) or restore the whole system (in case the whole thing crashes).
Photo by Markus Tacker