You should be talking about the barcode number. Books in the library have two bar code numbers. One is the barcode number of the book itself, which is the product number when the book was published. The other is the numbering carried out by the library for unified management of book borrowing, such as handing it over to amplt；; Xinhua dictionary ampgt；; The number is 123456789, and then input amp into the computer in the library; lt； Xinhua dictionary ampgt；; The corresponding number is 123456789, which is generated by the barcode generator and posted on the book. When borrowing or returning Xinhua Dictionary, the library staff will use the barcode scanner to illuminate the barcode, and the computer will display 123456789, and the related item is Xinhua Dictionary. Another number of books in the library is compiled for the convenience of book classification. The daily book flow in the library is so high.