The library loan system automatically renews your loans at the end of each loan period. When someone queues for the book, or when you have reached the maximum loan period, the book cannot be renewed and you will receive a message from the library.
If there is no queue for the book, you can return it and then borrow it again, but it always needs to be brought to the library.
When you receive a notification from the library that the book should be returned, you always need to hand in the book.
