What is heavenly stem? What is the earthly branch? Do they represent time or the zodiac?

The manifestations of heavenly stems are: A, B, C, D, E, G, Xin, N, G.

The earthly branches are as follows: Zi, Ugly, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu and Hai.

Ten branches and twelve branches are matched in turn to form 60 basic units, which are matched with each other in a fixed order, with the date year, month, day and hour. They represent the method of recording time.

12 earthly branches correspond to the zodiac: rat, ugly cow, tiger, rabbit, dragon, snake, afternoon horse, sheep, monkey, chicken, dog and pig.