The number nine starts from the second half of June and the winter solstice of 65438+February in the solar calendar every year, which is a more suitable solar term in northern China, especially in the middle and lower reaches of the Yellow River.

From the day of winter solstice, it entered the "number nine", commonly known as "cross nine", and then every nine days as a unit, called "nine". After nine "nines", it happens to be 8 1 day, that is, "nine out", and then spring blossoms.

In ancient China, especially the working people of the Han nationality in the north, the conditions for keeping warm from the cold were simpler than their descendants, and they regarded the cold winter as a threat and punishment from heaven. People even think that winter is inexplicably long, and the fear of freezing in the cold directly affects people's mood.

In order to survive the long and harsh winter, people invented the method of "counting nine" to pass the time to alleviate the psychological crisis under the threat of winter. At that time, counting nine around your family was also regarded as a carefree state, and this custom has been passed down to this day.