December 21 marks the start of dongzhi, or winter solstice, the 22nd of the 24 solar terms on the traditional Chinese lunar calendar. On this day, the Northern Hemisphere experiences the shortest day and the longest night of the year, as the sun shines directly at the Tropic of Capricorn. Dongzhi also marks the coming of the coldest period of the year. People in China also worship their ancestors during this time. Are you curious about how this solar term is interpreted in different Chinese calligraphy styles? Watch this video to find out.