Depression is a common disorder worldwide.In the West,depression is also called “the blues” informally.It is a psychological disorder characterized by an all-encompassing low mood.Slightly depressed people may behave normally,while experiencing feelings of pain at heart.In mild depression cases,people may feel gloomy or distressed,which is usually associated with memory impairment,insomnia,dreaminess,etc.People suffering from severe depression may be preoccupied with,or ruminate over,thoughts and feelings of worthlessness,inappropriate guilt,helplessness,hopelessness,hallucinations,or delusions,most often accompanied by recurrent thoughts of death,suicide attempt or a specific plan for committing suicide.With the intensifying pressure and a competition of modern society,many people become victims of depression.It brings great trouble and burden to patients,their families,and society.