冬至是中国二十四节气之中的一个重要节气，更是中华民族的一个传统节日。
The Winter Solstice is one of the 24 solar terms in the traditional Chinese calendar and also a significant traditional festival of the Chinese people.
冬至这一天，太阳直射南回归线，北半球的白最短，黑夜最长。过了冬至，太阳直射点就慢慢向北移动，白天会越来越长。
On this day, the sun shines directly over the Tropic of Capricorn, resulting in the shortest daylight and longest night in the Northern Hemisphere. After the Winter Solstice, the sun's direct rays gradually move northward, and the days become longer.
“冬至大如年”，古人认为这一天为藏之终、生之始，是大吉之日，故称其为“亚岁”“冬节”“长至节”等。“冬至不端饺子碗，冻掉耳朵没人管”，北方有冬至日吃饺子的习俗，认为饺子有“消寒”之意；在江南地区人们习惯吃汤圆，“圆”意味着“团圆”“圆满”。
The saying "Winter Solstice as grand as the New Year" reflects how ancient people regarded this day as the end of preservation and the beginning of growth—a day of great auspiciousness. Thus, it is also called "Sub-Year", "Winter Festival", or "Longest Day Festival". There is a Northern saying, "If you don't eat dumplings on Winter Solstice, no one will care if your ears freeze off", highlighting the tradition of eating dumplings on this day, believed to ward off the cold. In the Jiangnan region, people prefer to eat tangyuan (sweet glutinous rice balls), as the round shape symbolizes reunion and perfection.
古人认为冬至是阴阳二气自然转换的重要时刻，“阴极之至，阳气始生”。简单来说就是寒冷到了极致之后，温暖就会慢慢回来。
Ancient people also considered the Winter Solstice a pivotal moment of transformation between yin and yang energies: "When yin reaches its peak, yang begins to grow". In simple terms, once the cold reaches its extreme, warmth will gradually return.