The black or the dark portion represents 'Yin' which is feminine and passive energy; and white represents 'Yang' which is masculine and hot. But each contains a spot of the other which symbolizes that although opposites, Ying and Yang cannot exist without each other. In Feng Shui, anything hilly or elevated is considered to be Yang and anything flat is considered to be Yin. Or in other words, Yang representing heat and light is rising and Yin representing cold and darkness descends. Feng Shui is also regarded as an effort to balance the influences of Yin and Yang in our environment. Both Yang and Yin are considered to be co-existent and co-dependent. As it is thought that Yin originated from Yang and Yang originated from Yin and their constant moving balance as they encircle and embrace each other is considered to be the ideal image of harmony.

Yin and Yang are the basic expression of the Ancient Chinese and the Yin-Yang symbols could be the earliest of abstract written language. It is equivalent to a bit in today's binary language. Each Yao (bit) represents either Yin (0), female force of nature, or Yang (1), male force of nature. The co-existence of Yin and Yang is present everywhere and they rely on each other because they are relative characters. The Yin-Yang philosophy is about -- Yin is inside Yang and Yang is inside Yin. The concept of Yin and Yang is the Chinese perspective of balance and continual change and can be considered as the most fundamental and profound theories of Feng Shui.

Yin and Yang which is a foundation theory for Feng Shui, supports many other theories including the Five Elements theory and the Environment. They are the examples of duality which are co-existent with both parts representing light and darkness or more properly opposites. The chart shows some of the many opposites that are depicted in such a simple symbol.