In acupuncture, needles stimulate specific anatomical locations of the body surface along the meridians; and those locations are typically referred to as acupuncture points or acupoints.


      Ancient Chinese discovered a total of 361 classical acupoints that are distributed at courses of 14 general meridians, as well as a certain number of extraordinary points, which lodge beyond the 14 general meridians. The acupoints are referred to either by their traditional name, or by the name of the meridian on which they are located, followed by a number to indicate what order the point is in on the meridian. A common point on the hand, for example, is traditionally named Hegu, and referred to as LI4, which means that it is the fourth point of LI meridian. Other examples of acupoints are PC6 (Neiguan), ST36 (Zusanli) and BL40 (Weizhong), which are well-known in treating illnesses on the head  (e.g. headache), chest (e.g. nausea), abdomen (e.g. heart burn), or back (e.g. lumbago), respectively.


However, during the past few decades, many newly discovered points (over one thousand) have been added onto the existing number of extraordinary points. Moreover, there have been extensive anatomical and histological studies on almost all of classical acupoints and extraordinary points. It has now understood that so-called acupoint is actually a small area instead of a spot, where denser nerve ending may lodge or certain nerve branches may pass.