Acupuncture[note 1] is a form of alternative medicine[3] in which thin needles are inserted into the body.[4] It is a key component of traditional Chinese medicine (TCM). TCM theory and practice are not based upon scientific knowledge,[5] and acupuncture is a pseudoscience.[6][7] There is a diverse range of acupuncture theories based on different philosophies,[8] and techniques vary depending on the country.[9] The method used in TCM is likely the most widespread in the United States.[3] It is most often used for pain relief,[10][11] though it is also used for a wide range of other conditions.
More details, pls see https://en.wikipedia.org/wiki/Acupuncture.