Writing text using ink was done by hand for centuries. Woodblocks began to grow in popularity and importance from around the 2nd Century AD in China. The production of woodblocks was labour intensive and mistakes were easy to make. This focus on human labour made text documents extremely expensive. But a potential solution arrived in the creation of movable-type printing by Bi Sheng in 1040 AD, which used ceramic materials and also wood. By the 12th Century, bronze movable type was being used in China.