Meridians and collaterals are the essential component parts of human body structure. The Circulation of qi, blood and body fluids, the visceral functions as well as their correlations all depend on the transmitting and regulating functions of meridians to integrate the human body into an organic whole.

The theory Of meridians, which is taken as an important component of the theoretical system of traditional Chinese medicine, concentrates on the study of the distribution: physiological functions, pathological changes of the meridians as well as their relationships b with the viscera, body constituents, sense organs and orifices, qi , blood and body fluids.

Physicians in the past dynasties ceaselessly contributed their clinical experience to tb supplement and enrichment of the theory Of meridians since it formed in Huangdi’s Canon of Medicine. The theory of meridians supplementary to the theory of visceral manifestations, qi, blood and body fluids, has been the theoretical basis explaining t the physiological activities and pathological changes of the human body and provides important guiding principles for clinical specialties, particularly for acupuncture,  moxibustion , massage and Qigong.