Card number, the last six digits of ID card. A library is an institution that collects, sorts out and collects books and materials for people to read and refer to. As early as 3000 BC, libraries appeared. Library has the functions of preserving human cultural heritage, developing information resources and participating in social education. The last six digits of account number, card number, password and ID card in the electronic reading room of Nanning Library. Electronic reading room is a modern multifunctional reading room based on computer technology and network communication technology, which integrates reading, consulting, training and service of electronic documents (such as disks, CDs, network services, etc.).