Chinese zodiac signs represent twelve different types of personalities. Traditionally beginning with the sign of the rat. Though the animal assigned for the birth year is not wholly who a person is, as there is also an animal assigned by the birth month called inner animals and by the birth hour called secret animals. These with a combination of five elements, make up 8,640 possible combinations for a persons personality trait, and all are considered important for the proper use of chinese astrology.
There are many versions of the story about the beginning of the zodiac, one such story begins with the rat being given the task on inciting the animals to report to the Jade Emperor to be selected for the zodiac. The cat being one of the animals selected was a good friend of the rat who tricked him into believing the banquet was a day later and the cat slept through it thinking it was not till the next day. When the cat found out he vowed to be the rats’ swore enemy for the ages.