The 24 Solar Terms is a part of the traditional Chinese calendar. The Chinese people divided a year into 24 segments based on the sun's position in the zodiac. Each segment, with a time span of 15 days, is called a solar term, which reflected the changes of the seasons, climate and phenology.

In the ancient days, the solar terms were important instructions for agricultural production as well as people's daily lives. For example, the "Start of Spring", "Start of Summer", "Start of Autumn" and "Start of Winter" divided a year into four seasons, and each season was divided into six solar terms. Some solar terms may mark things like temperature, growth of the crops, and weather conditions, such as “Minor Snow”, “Winter Solstice”, and “Major Cold”.