The Dai ethnic group is the only ethnic group in Xishuangbanna that has its own written language, which is called "Dai Lai language". It is not clear when it came into being and who created it. Chinese historical records of the Yuan Dynasty all record: "There are hundreds of barbarians with gold teeth, and their records have no writing, and they are carved on wood." By the Ming Dynasty, the "Biography of Hundreds of Barbarians" said: "There are no Chinese characters, small things are carved on bamboo and wood, and big things are carved on wood." The books are all written by others." The "Burmese script" mentioned here may be Dai script, because both Dai script and Burmese script are written from left to right. Perhaps the author of "The Story of Baiyi" did not understand Burmese and Dai characters, and mistook it for Burmese. Therefore, the Dai language may have been used between the Yuan and Ming Dynasties in the 14th century, that is, about six to seven hundred years ago. The writing system of the Dai people was introduced with the introduction of Theravada Buddhism. It originated from the Pali script of ancient India and was formed through continuous transformation. It may have been introduced at the same time as Buddhism, or it may have lagged behind, that is, the Buddhist scriptures were first recited orally.
As for the carrier of Dai characters, in addition to modern paper writing among the people, the main ones used to copy Buddhist scriptures are "tissue paper" and "bay leaves". Tissue paper is made of paper mulberry growing in the forests of Xishuangbanna. The bark fibers of Broussonetia papyrifera are used as raw materials and are made using ordinary hand-made papermaking techniques. The paper is white and has good toughness and can be preserved for a long time. During the renovation in recent years, a 100-year-old paper was found at the Many'e Temple in Menglun. The document about the construction of the temple is written on tissue paper, and the handwriting is still as clear as ever. The bay leaf is taken from the leaves of a plant called Corypha umbraculifera, and is made through a special production process. The scriptures are engraved on it. Tie it together with a rope and it can be preserved for hundreds of years. Bay leaf palm does not grow in the tropical rain forests of Xishuangbanna. It was introduced with the introduction of Buddhism because it was the main carrier for (carving) scriptures. Due to the climate here, it is often cultivated in the courtyards of Buddhist temples and is very tall.