The Chinese Zodiac is a 12-year cycle. Each year of the 12-year cycle is named after one of the original 12 animals. Each animal has a different personality and different characteristics. The animal is believed to be the main factor in each person's life that gives them their traits, success and happiness in their lifetime.
The Chinese zodiac refers to a pure calendrical cycle; there are no equivalent constellations like those of the occidental zodiac. In imperial times there were astrologers who watched the sky for heavenly omens that would predict the future of the state, but this was a quite different practice of divination from the popular present-day methods.