According to legend, there was a disciple named Cheng Miao in Qin Dynasty who was imprisoned for offending Qin Shihuang. Cheng Miao saw that it was very troublesome for prison officials to write Yao cards with seal script at that time, so he carried out reforms, simplified the complex, rounded the square and created new fonts. Qin Shihuang saw it and appreciated it. Not only did he absolve himself of his sins, but he also made him an empire and used this font in official prisons. Because Cheng Miao is a slave, it was originally designed for the application of slave clothes, so it is called official script. There may be many indirect factors in this story. In fact, just like the emergence of calligraphy, official script is created by many people over a long period of time, and what Cheng Miao did was probably to sort out his works.