Depression is a mood disorder that causes a persistent feeling of sadness and loss of interest. Also called major depression, major depressive disorder or clinical depression, it affects how you feel, think and behave and can lead to a variety of emotional and physical problems. You may have trouble doing normal day-to-day activities, and depression may make you feel as if life isn't worth living.
More than just a bout of the blues, depression isn't a weakness, nor is it something that you can simply "snap out" of. Depression may require long-term treatment. But don't get discouraged. Most people with depression feel better with medication, psychological counseling or both. Other treatments also may help.