The channels of qi

The meridians are the channels along which qi, the vital energy, is described as flowing in Chinese medicine, each associated with an organ and a position in the yin-yang scheme. Twelve principal meridians are paired with the organs and run in a daily circuit through the body; eight extraordinary vessels form a deeper reservoir, and the network connects the interior organs to the surface points used in acupuncture.

The meridian system is the map on which acupuncture, acupressure and related therapies work, locating the points at which qi can be influenced and describing how a disturbance in one organ or channel affects the rest.