1. Obsessive-compulsive disorder (OCD) manifests itself as an unrelenting, lingering thought, impulse, or behavior. The patient believes that these symptoms are irrational, but cannot control the compulsive thinking or compulsive behavior. 2, OCD mainly includes obsessive-compulsive thinking and compulsive behavior. The content of compulsive thinking can be varied, such as the uncontrollable need to think about meaningless issues, or some disturbing and unethical content, if encountered with such content patients will feel very self-conscious. The most common compulsive behaviors are washing hands, or closing doors, turning off utilities, and so on. It is important to note that ordinary people also engage in these so-called compulsive behaviors. An important point of identification is that ordinary people do not feel that their thoughts are unnecessary but uncontrollable and that there is no psychological conflict or contradiction. Rather, they go about these behaviors with peace of mind.