Acupuncture (zhēncì, 针刺) is considered an alternative medicine, even if not scientifically verified, that uses specific needles inserted inside some points of the human body. The goal of these needles is to bring the individual back to the state of health and well-being. By dividing the body into meridians, the one who practices punctures tries to correct the imbalances in the flow of qi (it is the name given to the "internal" energy of the human body). The origin of this practice is uncertain. The first references to this medicinal technique date back to around 305 and 204 BC. Along with the diet, phytotherapy, massage therapy and some psychophysical gymnastics such as Qi Gong and Tai Chi, acupuncture is a cornerstone of traditional Chinese medicine.