It should be said that it is a law post. Before the invention of paper, most of the ancients wrote words on thin and slender pieces of paper made of bamboo or wood, which were called bamboo slips or simplified books. Or write it on silk, which is called a post. After the invention of papermaking, any short words written on paper or silk are called stickers. In the Tang Dynasty, due to the emperor's love, there appeared a collection of posts imitating the ink of predecessors, such as Long Live the Sky. In the Song Dynasty, there was a kind of seal engraving, which collected the calligraphy ink of famous calligraphers in past dynasties, carved it on stone or wood, and then unfolded it into an ink book, mounted it into a book or volume. Even if ancient calligraphy can spread and expand its influence, this kind of seal cutting is also a model for learning calligraphy, so it is also called calligraphy.

During the Ming and Qing dynasties, with the development of printing industry and people's demand for calligraphy learning, the calligraphy ink of predecessors was collected, and the calligraphy posts were continuously engraved and the scale was increasing. In addition to the above-mentioned "Long live the Heaven", there are other famous legal posts in history, such as Chunhua Pavilion post, Jiangtie post, Tantie post, Daguan post, Baojinzhai post, Zhenzhangzhai post, Stopping Yunge post, Yuqing Zhai post, Mo Chi Tang Xuan post, and Quick Tang Xuefa book.