The Pre-Qin period is the initial stage of Chinese calligraphy. Inscriptions found on Shang Dynasty oracle bones formed the earliest known system of Chinese written characters. From the point of calligraphy, inscriptions on the oracle bones and bronze vessels bore special aesthetic value, such as the beauty of lines and style. In the Western Zhou Dynasty, the ancient seal script came into being and then flourished in the bronze inscriptions. From the late Shang Dynasty through the Qin's unification of China, the overall trend in Chinese characters' transformation is their gradual simplification, with abstraction going up and pictography elements declining. Calligraphy developed considerably during the process of the transition of every single character.