The Chinese calendar
The Chinese calendar is lunisolar, incorporating elements of a lunar calendar with those of a solar calendar. It is not exclusive to China, but followed by many other Asian cultures. It is often referred to by the Western cultures as the Chinese calendar because it was first perfected by the Chinese around 500 BC . In most of East Asia today, the Gregorian calendar is used for day to day activities, but the Chinese calendar is still used for marking traditional East Asian holidays such as the Chinese New Year (Spring Festival, not to be confused with Lunar New Year, which is the beginning for several lunisolar calendars), the Duan Wu festival, and the Mid-Autumn Festival, and in astrology, such as choosing the most auspicious date for a wedding or the opening of a building. Because each month follows one cycle of the moon, it is also used to determine the phases of the moon.
In China, the traditional calendar is often referred to as "the Xia Calendar", following a comment in the Shiji which states that under the Xia Dynasty, the year began on the second new moon after the winter solstice. (At times under some other dynasties in ancient China, the year might begin on the first or third new moon after the winter solstice.) It is also known as the "agricultural calendar" while the Gregorian calendar is known as the "common calendar". Another name for the Chinese calendar is the "Yin Calendar" in reference to the lunar aspect of the calendar, whereas the Gregorian calendar is the "Yang Calendar" in reference to its solar properties. The Chinese calendar was also called the "old calendar" after the "new calendar", i.e. the Gregorian calendar, was adopted as the official calendar. Since the time of Emperor Wu of Han, starting the new year on the second new moon after winter solstice has been the norm for more than two thousand years.
According to traditional beliefs, some form of the calendar has been in use for almost five millennia. Based on archaeological evidence some form of it has been in use for three and a half millennia. It is reckoned in the seldom-used continuously numbered system as 4705, 4706, or 4645 (depending on the epoch used).
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