Korean calendar - Wikipedia
https://en.wikipedia.org/wiki/Korean_calendar• The Chinese zodiac of 12 Earthly Branches (animals), which were used for counting hours and years;• Ten Heavenly Stems, which were combined with the 12 Earthly Branches to form a sixty-year cycle;• Twenty-four solar terms (jeolgi / 절기, Hanja: 節氣) in the year, spaced roughly 15 days apart;