When you checkmark a book, by default it marks it read. On this page you can do advanced book management.
Read Status: by default, it is marked as read. You can change the status to Did Not Finish if you started the book and didn't finish it, or add it to your Want To Read list. Finally if you don't want it to show up across the site as a book still to read by the author, you can mark it as Not Interested.
Private Notes: If you wish to make any private notes related to the book, you can do so within this section. These are not listed anywhere on the site.
Public Rating: In this section you can rate the book out of 10. This rating will affect the overall rating of the book which is displayed on the site.
Public Reviews: Loved the book and want to write about it? You can write up a review which will show up at the bottom of the authors page. We love reading reviews and they help other readers, so reviews are much appreciated! No spoilers in the reviews though please.