1. The "DRM-Free backup copy" applies to comics from Comixology (from certain publishers), not to comics bought in Amazon for the Kindle or to ebooks for the Kindle.

2. You can't donwload ebooks directly from the web. You need to send them to your Kindle or download them using a Kindle application.

3. For most publishers, Kindle ebooks can't be read using other software and can't even be transferred to other Kindle or Kindle computer, they are encrypted and tied to the Kindle or Kindle app you downloaded with.

4. Some publishers, like Tor, sell their books without DRM. See "Ender's Game" from Tor. These books can be open with other software that supports Mobi, can be transferred betweeen devices or computers or they can be converted to other formats.

Thanks for the summary. So I feel that I was right to be surprised by Comixology's move. The new ability to download is closer to the GOG model while DRM-free e-books are closer to DRM-free on Steam. (IMO.)

So how does this work?

Whats a PDF or CBZ format?

Also I have made purchases of Comic Books in this website long before. So do I still get DRM free versions of books I already purchased?

PDF is a standard format from Adobe that's very common for documents. CBZ is basically a zip archive of page images.

Yes, if you have comic books form a DRM-free publisher you'll be able to download then from the backup tab.

Where is the backup tab? I checked my books and I don't see an option to download digitally?

(Sorry for not replying sooner)

Ah, can post today. I answered by PM, but the short of it is go to your books on Comixology and you'll see the backup tab.