What's with the birthday?

In ancient China, there was the heavenly stems and earthly branches Chronology Law, that is, ten days of dry A, B, C, D, E, Ji, Ke, Xin, Ren and Gui; Twelve earthly branches, ugliness, yin, Mao, Chen, Si, E, Wei, Shen, You, Xu, Hai; Pairs form sixty jiazi. You can record the year, month, day and hour separately.

According to China's ancient chronology of cadres and branches, the date, month, date and hour of a person's birth are recorded in two words, such as Geng Xu, Chen Wu, Jia Zi, Ji Chou and * * *. In ancient China, fortune-telling was based on people's "birthday" to measure good or bad luck, wealth, poverty and future, so fortune-telling was also called "criticizing eight characters" or "pinching eight characters".