The term acupuncture describes a family of procedures involving stimulation of anatomical points on the body by a variety of techniques. The acupuncture technique that has been most studied scientifically involves penetrating the skin with thin, solid, metallic needles that are manipulated by the hands or by electrical stimulation. Acupuncture needles are metallic, solid, and hair-thin. People experience acupuncture differently, but most feel no or minimal pain as the needles are inserted. Some people are energized by treatment, while others feel relaxed.