Traditional Chinese Medicine (TCM) has been practiced for more than two thousands years. Its theoretical system was partly derived from the philosophy that informs Taoist and Buddhist thought and complemented through practice. The basic theories include Yin and Yang, the five elements, Zang-Fu theory, theory of Qi, blood, and body fluid, theory of meridians and collaterals, and theory of etiology and pathogenesis, etc. These theories have been applied to diagnosis of diseases