Yin and Yang are two forces that represent all aspects related to life. The outer side of the circle represents everything in the Universe while Yin the dark side of the circle represents:
And Yang the light side of the circle represents:
Yin and Yang are the interactions between the two forces and represent how life is a mixture of good/bad and highs/lows. Yin and Yang ties into the Zodiac by assigning a Yin or Yang force to each element. The Vietnamese names for Yin and Yang are:
Am (Yang) and Duong (Yin).
Determining if your birth year is Yin or Yang
Based on the info above, you can determine your Yin or Yang symbol by looking at your year of birth and seeing if it ends in an odd or even number.
Ex: If I was born in 1986, since 6 the last digit of the year is even I am considered a Yang.