What is mental illness? The so-called mental illness is a class of common complex diseases characterized by abnormalities in cognition, emotion, will and behavior, including schizophrenia, manic depression, affective disorders, anxiety disorders, dementia, obsessive-compulsive disorder, autism, alcohol, drug or other substance dependence, eating disorders, etc. Psychiatric disorders often lead to reduced ability to work, inability to take care of oneself and difficulties in interacting with others. The accompanying psychological factors such as fear, anxiety, tension and despair are in turn important causative factors for cardiovascular diseases, hypertension, malignant tumors, ulcer diseases, etc. In addition, psychiatric disorders may bring indirect adverse effects such as social discrimination and self-guilt to patients and their relatives. The etiology of psychiatric disorders has not been fully elucidated so far. Most studies have shown that the etiology of mental illness is not a single causative factor, but a combination of factors, including biological, environmental, psychological, and social factors. It is estimated that there are currently 450-500 million people worldwide with various types of mental and brain disorders, i.e., 1 in 4 people will develop some kind of mental disorder at some point in their lives. Mental illnesses generally have a slow developmental process, and some are relatively easy to correct, while others are more difficult to treat and require long-term formal systemic treatment, but most patients can recover and maintain basic integrity of social functioning and interpersonal relationships. Therefore, mental illness is not terrible, what is terrible is not to pay attention to it and not to treat it. In short, once a family member is found to have psychiatric symptoms, he or she should go to a regular hospital for treatment and timely recovery.