In ancient times, writing works and inscriptions were generally written on tablets of bamboo or on pieces of silk. But silk being costly and bamboo heavy, they were both not convenient to use. Then Cai Lun initiated the method of making paper with the bark of trees. Traditionally, he is regarded as the inventor of paper and the technique of papermaking. Although early forms of paper had already existed in China since the 2nd century BC, he fostered the first significant improvement and standardization of papermaking by adding essential new materials into paper's composition. Cai found the composition of paper and invented the technique of papermaking. Cai was reputed for this invention in the world, and even in his own lifetime he was already given recognition for it.