What is Yin Yang:
The yin yang is a principle of Chinese philosophy, where yin and yang are two opposite energies that are needed and complemented, the existence of one depends on the existence of the other. The yin and yang is a symbol of harmony due to the balance produced by the interaction of the two energies.Yin Yang
The yin yang are two concepts of Taoism, which exposes duality of everything that exists in the universe. Yang is a luminous, positive energy that presents itself intensely, whereas yin is a passive, negative light. Each object or situation is related to these two dualities and feng shui is in charge of finding a balance to achieve well-being and fortune.
Some authors relate yin yang to light and sun, male and female, but they are mistaken definitions since Taoism is basically composed of positive or negative energy. The two spheres within the symbol represent the idea that each of the forces reaches its extreme point and manifests within itself an opposite feeling.