1. The hour is the ancient time unit. The ancient people divided a day into twelve hours, and each hour is equal to two hours now.
2. It is said that each hour is named according to the appearance time of animals in the zodiac.
3. According to the order of the twelve local branches, a day is divided into twelve periods, namely Zi, Chou, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu, Hai, which are called Shichen.
