Some people interpret that the first step to fully implement paperless teaching system is to start with teaching materials and enable paperless teaching. Traditional textbooks are published on paper. Electronic teaching materials store documents on the server or terminal through digital technology, which has the advantages of low cost, small occupied space, large storage capacity, rich content, strong interactivity and powerful retrieval function. It can greatly save natural and social resources, facilitate students to find needed resources quickly, and improve learning interest and efficiency.