DRM refers to the fact that you can't view Amazon Kindle books on other devices (including your computer), or on other Kindles - i.e. no sharing, the purpose of DRM.
The Kindle only allows the reading of Amazon DRM-protected content.
The Kindle has many flaws, but it does allow you to read a few different non-DRM formats.
How do you load other eBooks onto the Kindle? Just add Amazon DRM.
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