Knowing the format and the protection of a book in iBooks
You can use iTunes to find out the format of the books on your iPad.


Install iTunes on your Windows PC.
Plug your iPad in to your Windows PC, iTunes should detect it and a button should appear in the top right of the iTunes window just under "Search Library". Click on the button for your iPad.
You should be presented with a long horizontal list of options including "Summary", "Info", "Apps", etc. Click on the last option called "On This iPad".
You should then see a list of options down the left called "Music", "Films", "TV Programmes", etc. Click on Books.
Now you should have a list of your books in the centre of the iTunes window. Right-click on the book you want to know the format of and select "Get Info".


The window that appears will tell you the "Kind" of book it is. If I remember correctly they are "Protected book" for IBA or EPUB books with DRM, "Puchased book" for IBA or EPUB without DRM and "Book" for PDF files.