CopyThe cheapest solution for an individual PC user who wants to back up data files would be back up to re-writeable CD's. If your PC does not have a re-writeable CD drive, you can easily install one yourself if you have a spare slot for it. If not, you can get an external re-writeable CD drive, but they cost more.
Alternatively you can back up to a USB data stick.
There are also lots of companies who offer an online backup service.
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