In light of Robin Williams' death, thought this would be a good pick.
Understanding Anxiety Disorders: Signs, Treatment, Diagnosis and Causes
Anxiety is a common emotion. Anyone can feel anxious, especially when exposed to stressful situations. Nonetheless, there are some people whose anxiety may be categorized as a disorder. A normal individual will react to a stressful event based on their individual capacity to withstand pressure. A person who is suffering from an anxiety disorder will deal with a trigger in different way.