When readers need to extend the borrowing time of borrowed books, they can only renew them once without other readers making an appointment. The renewal period is 30 days. Overdue books are not accepted for renewal. New books can be renewed once that year for a period of two weeks.

Take the National Library as an example:

1. Renewing the loan can prolong the time of books in personal hands as much as possible.

2. Renewal is not a service worthy of promotion. Need to go through the formalities twice. The renewal system can guide individual reading behavior (such as time) to a certain extent.

3. The renewal of the national map is accompanied by the appointment system. A has a book, and B can't renew it by appointment (within the first borrowing time of A). This increases the circulation rate of books.

Generally speaking, the number of books used for borrowing in the library is relatively low, and most of them are single books, mainly new books. This kind of collection is convenient for readers to chase and borrow hot books. Renewing books can basically ensure that popular books will not be around for too long.

4. Renewing the loan is generally a computer operation. How many old people or people who can't use computers often become interested in computers after several times? It is helpful for the popularization and use of new technologies.