Anxiety

Anxiety is a feeling of nervousness, apprehension, fear, or worry. Some fears and worries are justified, such as worry about a loved one or in anticipation of taking a quiz, test, or other examination. Problem anxiety interferes with the sufferer's ability to sleep or otherwise function. It is noteworthy that teenagers are particularly susceptible to having irritability as a symptom of a number of emotional problems, including anxiety. Anxiety may occur without a cause, or it may occur based on a real situation but may be out of proportion to what would normally be expected. Severe anxiety can have a serious impact on daily life.

Anxiety is a generalized mood condition that can often occur without an identifiable triggering stimulus. As such, it is distinguished from fear, which is an emotional response to a perceived threat. Additionally, fear is related to the specific behaviors of escape and avoidance, whereas anxiety is related to situations perceived as uncontrollable or unavoidable. Another view defines anxiety as "a future-oriented mood state in which one is ready or prepared to attempt to cope with upcoming negative events", suggesting that it is a distinction between future vs. present dangers which divides anxiety and fear.