Why do I need to borrow certain titles?
Due to licensing agreements, some titles have limited availability. When you open one of these titles, you're borrowing a copy for a limited period of time.
Borrowed titles have on the title card and are listed under My books > Borrowed.
If all of the copies for a title are in use, you can place a hold instead. Once the title is available, it will be automatically borrowed for you and you'll get an email notification.