Sitting for a long time, back pain; excessive brain use, headache; eat cold things, may have a toothache; after surgery, will feel the paroxysm of pain; some diseases, but also triggered by pain all over the body …… “Pain” is the earliest people experience in life, but also feel the most subjective feeling! For some common pain, many people have been accustomed to, and even do not take it for granted. Pain, acute pain and chronic pain. Acute pain caused by the primary disease, with the cure of the primary disease, the pain also disappears. For example, post-surgical wound pain, wound healing, the pain is also relieved. Chronic pain is often cured after the primary disease, the pain still persists, and progressive aggravation trend. At this time the body’s pathology and physiological changes with the primary disease is completely different, such as part of the herpes zoster patients, herpes has disappeared, but the pain is still prolonged for several years or even lifelong. The World Health Organization has clearly pointed out: acute pain is a symptom, chronic pain is a disease. Clinically, the disease with “pain” as the main symptom is called “pain disease”.