Almost everyone has had a headache at one time or another, with 90% of people experiencing a headache within a year and only 1% being spared for life. There are 28 million migraineurs in the U.S. and 600 million migraineurs worldwide each year. 5% of women and 2.8% of men have a headache for 180 days or more each year, and television commercials promoting various medications for headaches are ubiquitous. Headache is the most medically diagnosed condition, with more than 300 different types and causes. Most headaches are primary headaches, that is, headaches without a clear cause, such as migraine, tension-type headache, cluster headache, etc. These headaches are often recurrent, often with spontaneous periods of remission, and some can be chronic for decades, causing great distress to physical and mental health, but often without fatal consequences. However, some headaches have a clear cause, which we call secondary headaches, and these headaches often lead to serious consequences because the primary headache is not treated in time. So how can we simply determine this type of headache? 1. The age of the headache. In general, migraine mainly starts before the age of 40, and headache that starts after the age of 40 needs to be paid enough attention. The possibility of primary headache in childhood is very small, and if headache appears in childhood, it needs to be paid attention. 2. Time of headache. The degree of headache, sudden burst-like severe pain, can be caused by subarachnoid hemorrhage, carotid artery entrapment aneurysm or migraine. Progressive aggravation of headache, including the frequency of pain attacks or progressive aggravation of the degree of pain, needs to be alerted to intracranial tumors and intracranial infectious diseases. 3.Pain site. For headache with fixed pain site, especially for headache that is ineffective to general pain relief treatment, secondary intracranial lesions should be excluded. 4.Concomitant symptoms. Headache with neurological symptoms such as vomiting, fever, nystagmus, unsteady gait, hallucinations, slurred speech, etc., and headache with seizures require head imaging to exclude organic lesions. If headaches with the above characteristics occur, it is important to seek prompt medical attention to rule out more serious secondary lesions. Of course, many headaches with malignant lesions can also exhibit benign headache characteristics in the early stages. Regardless of the manifestation of headache, early medical attention is necessary to rule out major lesions.