The Chinese Zodiac consists of a 12-year cycle. Each year is named after a different animal. Each cycle starts from the Rat, then by sequence are: the OX, the Tiger, the Hare, the Dragon, the Snake, the Horse, the Sheep, the Monkey, the Rooster, the Dog, and ends to the Boar. Every twelve years, the cycle of animals starts over again.
It is because that Chinese has 12 Earthly Branches. Besides the 12 Earthly Branches, Chinese has 10 heavenly stems referred yin-yang principles and the 5 elements: wood, fire, earth, metal and water. The two sets were used together to enumerate years and other elements of the civil, or official, calendar. The 10 stems and 12 branches were used together to create a cycle of 60 two-symbol combinations. The complex calendar is called the sexagenary cycle. During the complete 60-year cycle, each of the animal signs (sometimes also referred to as the 12 Earth Branches) is associated with the five main elements: Wood, Fire, Earth, Metal and Water. A fundamental part of Oriental philosophy is the interrelationships among the five elements. The element of your lunar sign will exercise their influence on your life.
Another saying about this is that according to legend, the Lord Buddha summoned all the animals to come to him before he departed from Earth. Only 12 animals came to bid him farewell. As a reward he named a year after each one in the order that they arrived.
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