Amazon and B&N cook their own with the DRM-schemes. Their formats can only be read by their devices or if you want to read them on a Sony you have to break the DRM and use Calibre.
Actually I am not sure the royalties go to the authors, I think they go to ADE for providing this DRM stuff. The idea is to make it hard for people to copy books and share them with friends so more books should sell. The reality is, it does not work like this.
You don't need Calibre (it) to read your books as long as you don't buy books with Amazon or B&N.
It is not hard to break it, actually it is easy, but I am not sure, if you should start like this. Maybe when you are more confident in handling everything else
