China National Digital Library China National Digital Library is the website of many e-books. The website provides books, periodicals, newspapers, papers, ancient books, music and movies for everyone. Click on its books and you will see many e-books. The e-books of college textbooks we need can be directly searched. For example, if we search for "College English", then you will see all the college English textbooks. If you want to download something, click the "Send Document" button to download it successfully, and the downloaded PDF document will be sent to your mailbox, provided that you need to log in to download it successfully. 2. China University Courseware Download Website This is a courseware download website with rich resources. With this website, it can be said that there is no university textbook that you can't find. The subjects offered are comprehensive and extensive, including: foreign languages, basic medicine, law, chemistry, biology, agriculture, machinery, computer, education, electronics and communication, mathematics, etc. You can find the e-book you need through search, or you can look it up directly on the website. The download method is also very simple. Just click on the courseware below and you will jump to the "Download Now" page. Click download. 3. Taobao is a website for searching university e-books for free. You can search all the e-books you want here and support free download. In addition to e-books, you can also find all kinds of ancient books, calligraphy and painting, teaching materials, and all the books you find can be downloaded. For example, if we search "calculus", we can see all the e-books related to calculus. Then we click on the calculus textbook we want to download, and the following will go directly to the download page, and click "Click here to download" to get it for free. 4. National Library Reference Alliance This is also a relatively comprehensive library website, which provides a very comprehensive e-book. We can find books, periodicals, papers, patents, science and technology newspapers, etc. Here, it also supports foreign search, and it is also a very useful document search website. Its subjects provide literature, science, education, physical education, history, geography, comprehensive books, language and so on. For example, if we search for college Chinese, you can find college Chinese courseware from various schools, including Peking University, Tsinghua University, Nanjing University of Science and Technology, Sun Yat-sen University, Wuhan University and so on. Each of its books is collected in the corresponding university library and can be obtained by clicking borrow. 5.Library Genesis is a super-rich foreign book website, which also supports duplicate checking of papers. The way to find the book we want is through the search function. Enter the author's name, title, book number and label to find the corresponding book.