The term "acupuncture" describes a family of procedures involving the stimulation of anatomical points on the body using a variety of techniques. The acupuncture technique that has been most often studied scientifically involves penetrating the skin with thin, solid, metallic needles that are manipulated by the hands or by electrical stimulation.
Practiced in China and other Asian countries for thousands of years, acupuncture is one of the key components of traditional Chinese medicine. In TCM, the body is seen as a delicate balance of two opposing and inseparable forces: Yin and Yang Yin represents the cold, slow, or passive principle, while yang represents the hot, excited, or active principle. According to TCM, health is achieved by maintaining the body in a "balanced state"; disease is due to an internal imbalance of yin and yang. This imbalance leads to blockage in the flow of qi (the vital energy pronounce "chi") along pathways known as meridians. Qi can be unblocked, according to TCM, by using acupuncture at certain points on the body that connect with these meridians. Sources vary on the number of meridians, with numbers ranging from 14 to 20. One commonly cited source describes meridians as 14 main channels "connecting the body in a weblike interconnecting matrix" of at least 2,000 acupuncture points.
Acupuncture became better known in the United States in 1971, when New York Times reporter James Reston wrote about how doctors in China used needles to ease his pain after surgery. American practices of acupuncture incorporate medical traditions from China, Japan, Korea, and other countries.