During the Western Zhou Dynasty, bronze smelting technology developed rapidly and a large number of bronzes were produced. The ruling class likes to carve words on these bronzes to praise the king or sacrifice. This kind of writing is called Zhong Dingwen, which is often referred to as epigraphy by later generations. Bronze inscriptions are more pictographic than Oracle Bone Inscriptions's, and retain the traces of early hieroglyphics. In the late Western Zhou Dynasty, Chinese characters evolved into Da Zhuan, and the font structure of Da Zhuan began to be neat, and the lines were concise and vivid, gradually deviating from the original state of lines. Compared with Oracle Bone Inscriptions and Jin Wen, Da Zhuan at this time has made great progress.