What is the QR code at the back of the book?

To spread the reading experience. Yueduji is the publishing house of Tibet Yueduji Culture Media Co., Ltd. After the books published by Yueduji Publishing House, there will be a QR code of Yueduji. The purpose is to spread Yueduji, let readers know Yueduji publishing house better, and search other high-quality books in Yueduji.