Caoshu (草书,cursive hand) is characterized by sketchy, simplified forms of characters, often distorted or exaggerated to achieve an internal rhythmic appearance within the compositions of characters. In theory, any character can be written in the style of caoshu, for instance many course characters appeared in inscriptions on bronze wares. However, caoshu in literature refers to a specific style developed from Qin lishu (official script), formed around the Western Han Dynasty (206BC-25AD) and prevalent in the Eastern Han Dynasty (25-220).
Caoshu in the early period retained much feature of lishu and was called zhangcao (a coarse style formed by breaking up the forms of lishu). From the Eastern Han Dynasty to the Wei (220-265) and Jin (265-420) dynasties, caoshu got rid of the trace of lishu strokes, and employed a large number of running strokes, and was called jincao (modern cursive hand). By the Tang Dynasty (618-907), caoshu was written in a lively and vigorous way and was called kuangcao (crazy cursive hand).
Because caoshu uses lots of running strokes and only has the outline of the characters, it is illegible to most readers and affects its function of communication. Famous caoshu calligraphers include Zhang Zhi, Zhang Xu, Huai Su and so on.
