A variety of theories exist to explain the condition of anxiety. To begin, anxiety is inescapable according to the existential theory. Existential theorists support the belief that anxiety is a normal part of life; therefore, everyone experiences it from time to time. Moreover, since existentialists believe in personal choice, each person has the ability to control how their anxiety affects them. In addition, behavioral and learning can also focus on anxiety. Typical anxieties can play a role learned through direct experiences and in direct observation; as a result, someone might see someone else do something then copy them and not even think about it. Although, theories such as avoidance on behavioral, and learning can eventually skyrocket to the next level; some phobias may occur, and become intense concurring to extreme behavior. Cognitive theories better known as thinking can interpret on how reactions can affect anxiety. Internal mental statements are tangible information if other anxiety emotions are felt; some individuals may be exposed on this innermost part of cognitive theory. Anxiety disorders are common for many patients today, and different classifications require medications to control themselves through cognition. All in all, anxiety can appear in almost everybody without even noticing it.