Ceramic products are a very ancient art form, with a history dating back to about 20000 years ago. China is known as the "Porcelain Country" and has a long tradition and outstanding skills in ceramic art and manufacturing. The development of Chinese ceramics reflects a continuous process of progress and innovation, from the initial red pottery, gray pottery, colored pottery, black pottery, white pottery, to later primitive porcelain, celadon, black porcelain, white porcelain, as well as color glazed porcelain, underglaze color, and overglaze colored porcelain.