The digital library built by CADAL project is mainly digital books and periodicals, covering the academic literature resources of all key disciplines. At present, the collection of Chinese and foreign books, periodicals, newspapers, papers, audio-visual materials and other digital resources is more than 2.7 million volumes/piece, including 540,000 kinds of periodicals, books and ancient books in the Republic of China, which has played a huge supporting role in teaching and research in colleges and universities. CADAL was the first choice for searching books in the late Qing Dynasty and the Republic of China. More than 6.5438+0.5 million e-books have been used, including nearly 6.5438+0.6 million books in the late Qing Dynasty and the Republic of China. Besides books, CADAL also includes ancient books, dissertations, periodicals of the Republic of China, newspapers, English and other resources. Ancient books and English books are open to all users, and registered users can also borrow a large number of other copyright-free literature resources for free through the digital lending mode.