text: The word paper comes from the ancient Egyptian writing material called "papyrus", which was woven from papyrus plants. \n\nPapyrus was produced as early as 3000 BCE in Egypt, and in ancient Greece and Rome. Further north, parchment or vellum, made of processed sheepskin or calfskin, replaced papyrus, as the papyrus plant requires subtropical conditions to grow. \n\nIn China, documents were ordinarily written on bamboo, making them very heavy and awkward to transport. Silk was sometimes used, but was normally too expensive to consider. Indeed, most of the above materials were rare and costly.\n\nArcheologically, true paper had been excavated in China dated from the 2nd-century BC. It spread slowly outside of China; other East Asian cultures, even after seeing paper, could not figure out how to make it themselves. Instruction in the manufacturing process was required, and the Chinese were reluctant to share their secrets. The technology was first transferred to Korea in 600 and then imported to Japan by a Buddhist priest.\n\nAfter further commercial trading and the defeat of the Chinese in the Battle of Talas, the invention spread to the Middle East, where it was adopted in India and subsequently in Italy in about the 13th century. They used hemp and linen rags as a source of fiber. The oldest known paper document in the West is the Missel of Silos from the 11th century.