There are a few types of depression. The first type of depression is called Major Depressive Disorder (MDD). Major Depressive Order is a mood disorder characterized by a number of key features, for example, depressed mood, changes in weight, changes in sleep, feelings of worthlessness and guilt, difficulty concentrating, and thoughts of death or suicide. The second type of depression is called Persistent Depressive Order. Persistent Depressive Disorder is a type of chronic depression present for more days than not for at least two years it can be mild, moderate, or severe.  Persistent Depressive Disorder includes feelings of sadness, loss of interest and pleasure, anger and irritability, feelings of guilt, low self-esteem, difficulty falling or staying asleep,  sleeping too much, feelings of hopelessness, fatigue and lack of energy, changes in appetite,  trouble concentrating. The third type of depression is called Bipolar Disorder. Bipolar Disorder is a mood disorder characterized by periods of abnormally elevated mood known as mania. Bipolar Disorder includes fatigue, insomnia, and lethargy, Unexplained aches, pains, and psychomotor agitation, Hopelessness and loss of self-esteem, Irritability and anxiety, Indecision and disorganization. The fourth type of depression is called Atypical Depression. Atypical depression is followed by a specific set of symptoms related to excessive eating or gaining weight, excessive sleep, fatigue, weakness, and feeling “weighed down”, intense sensitively to rejection, and strongly reactive moods.

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