What does it mean to have your hair cut in the first month?

According to legend, after the Qing dynasty entered the customs, people in the previous dynasties were required to shave their hair and braid their hair. Many Han people who miss Han Chinese rule but dare not openly oppose the imperial court leave their hair in the first month to show their memory. Over time, there is a saying that "my uncle died in the first month."

Hairdressing in the first month, a popular word on the Internet, is the saying that my uncle died in many places in China. The word "etymology" originated from the Qing Dynasty, when the Qing Dynasty imposed a haircut order for the need of ruling ideology. However, the concept of Han people has always been healthy and influenced by their parents. Don't cut your hair if you can't cut it. This is the best question.

The first month after the lunar calendar:

Later, the relevant month of the lunar calendar was called the first month of the lunar calendar, and the first month of the official calendar was silver moon, including beginning of spring and rainfall in the 24 solar terms. The first lunar month is the first lunar month when the main time in beginning of spring is 15 or 16. If you come late, you should add a lunar month as a leap month in the year before the lunar calendar, otherwise it will not match.

The first month of the solar calendar used in mathematics books: The so-called "building the yin in the first month" in ancient and modern mathematics literature does not refer to the lunar calendar, but refers to the lunar calendar that began on the first day of spring. In mathematics, the so-called "being robbed in Shanghai in the first month" refers to the solar calendar. If you don't understand these two first months, you won't understand mathematicians' books.