1. Development stage: From the Yin Shang Dynasty to the Western Han Dynasty, this is the origin period of calligraphy, and Oracle Bone Inscriptions and bronze inscriptions are the main writing forms at this stage, with pictographic characteristics.
2. Mature stage: From the Eastern Han Dynasty to the Southern and Northern Dynasties, the birth of official script and the finalization of regular script, running script and cursive script marked the maturity of calligraphy art. Official script simplified the strokes of seal script, increased the change of thickness and length on the basis of the original equal thickness, and produced different shapes of horizontal, vertical, left and right.
3. Prosperity stage: Since the Sui and Tang Dynasties, calligraphy art has diversified into calligraphy styles, and the development of fonts has ended. However, the art of calligraphy is still developing and innovating, creating various styles and schools by integrating various elements.