Contributions by Tsai Lun, the paper inventor, are as follows; 1. As most of the materials, which were used, were the waste articles, the cost was cheap and the large quantity could be produced at a time. 2. It was much more convenient to use or carry them beyond comparison with the existing materials. 3. He established how to manufacture the paper if which the materials is vegetable fiber and invented a successive paper making. 4. He extended the kinds of paper manufacturing materials by instructing the worker about how to make the bark paper from the paper mulberry fiber, namely, he tried to realized the technological renovation to connect the past and the future. 5. As a result of his efforts, he greatly contributed to the social development as the supply of books and knowledge was smoothly active, and the paper is the best and ultimate one as the writing material.