What is the best way to backup epub and pdf books in iBooks? If you are going to format your computer, and you are running OSX 10.10 or newer, what is the best way to backup epubs and pdfs that weren't purchased from the iTunes store? 


I have a lot of books, exporting them one by one could take a long time. 
I'd ideally like to preserve highlighting and bookmarks. 


Google unfortunately returns surprisingly little information on how to backup ibooks.
Your books and book metadata are stored in…

~/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks/Books


Backup this entire directory to backup all your books.