The main symptom of depression is a low mood, which is experienced by more than 90% of people with depression. It can range from poor mood, upset, distress and sadness to pessimism and despair. The facial expressions are quite characteristic, with tightly locked brows, dull gaze, staring at the ground without blinking for less than an instant; casual and unkempt clothing. The depressive mood cannot be changed by anything outside, such as a long goodbye to an old friend or a promotion or salary increase. However, there are a few patients who do not experience depressed mood, but show somatic discomfort, which should be more attention. Patients with depression often appear tired and weak, feel a lack of energy, lack of motivation and initiative. At this time, although patients know what to do and how to do it, but feel powerless and incompetent. In work, they procrastinate, backlog, and lose efficiency; in life, they are too lazy to take care of household chores, and in serious cases, they even ignore food, drink, and personal hygiene. The patient is unable to pick up his or her spirits and becomes increasingly lethargic and exhausted. Low self-esteem is a unique way of thinking for depressed people. Total denial of oneself is the root cause of feelings of worthlessness (uselessness), self-blame and guilt, shame and pessimism. Patients reflect on past experiences, often blaming themselves for insignificant things. They do not have any hope for the future and believe that they will be a failure, with no hope for the future and no light in sight. In severe cases, the person feels hopeless, that everything is bad for him or her and that he or she is worthless. Only see the negative side of what is happening now, it seems to put on the “gray glasses”. As a result of this mindset, many people will develop suicidal ideas, and in severe cases, they will take suicidal behavior or even die by suicide, causing unbearable damage.