There are allusions to "Five Clouds" in the history of signature. In the early Tang dynasty, the signing ceremony generally only cursive a person's surname, first name or first name. As a private note, it is called "Shu Hua", and the words "pledge" and "ten" are not written. Wei Li, the son of Wei Anshi, who was famous for his "Hua Shu" in the Tang Dynasty, was a minister of rites in the two dynasties. When he was in office, he just signed the document and claimed that his book was like Five Clouds, and later people called his book Five Clouds.