About the Kindle Format (Amazon)

Amazon sells E-books in its own proprietary format, not the standard EPUB format used by most other stores (e.g. Apple’s iBooks store or Kobo).

Why does that affect me?

Amazon-purchased e-books work fine on Amazon's own Kindle readers. However, if you want to use any other reader or a non-Amazon reading program, it may not support Amazon’s proprietary format.

To my knowledge, EPUB files sold by other stores are supported by a much more wide range of devices and software, including Amazon’s own Kindle Previewer that according to Amazon allows a conversion for the Kindle. Make of that information what you will!

Disclaimer: this is based on my personal experience as a reader, and I put this here as a piece of advice to other fellow readers. However, I’m not an infallible e-book expert — let me know if something here is wrong.