Traditional Chinese medicine (also known as TCM or T.C.M., Simplified Chinese: 中醫學; Traditional Chinese: 中醫學; pinyin: Zhōngyī xué) is a range of traditional medical practices used in China that developed during several thousand years. It is a form of Oriental medicine, which includes other traditional East Asian medical systems such as Japanese and Korean medicine. TCM says processes of the human body are interrelated and constantly interact with the environment. Therefore the theory looks for the signs of disharmony in the external and internal environment of a person in order to understand, treat and prevent illness and disease. TCM theory is based on a number of philosophical frameworks including the Theory of Yin-yang, the Five Elements, the human body Meridian system, Zang Fu theory, and others. Diagnosis and treatment are conducted with reference to these concepts. TCM does not usually operate within a scientific paradigm but some practitioners make efforts to bring practices into an evidence-based medicine framework.