Some people who suffer from anxiety can still effectively adapt with their environment, while some are unable to control it and causes it to affect their lives. The degree of how it affects the lives of people varies.
Here are the 2 major classification of anxiety:
1) Adaptive anxiety

Not all forms of anxieties are bad for you. Sometimes you a little amount of anxiety can enhance your efficiency and achievement. Entertainers such as singers usually have anxieties before performing in the public. This increases their awareness and eventually helps them in performing. By becoming more aware they are most likely to avoid mistakes and thus giving a better performance. The ability to tolerate and use their symptoms makes it highly adaptive.
2) Maladaptive anxiety.
In contrast, a maladaptive anxiety interferes with their efficiency and achievement. Often their anxieties pose as a limitation in their life making it impossible for them to take advantage of the opportunities that are in front of them. For example, an aspiring singer is about to go into stage. Just before her performance she experienced having thoughts on making a mistake. Unable to control her fear, she starts to sweat and palpitate. It even causes her voice to change instantly. She now starts to panic and walks back in forth. Then she decides that she can’t do it after all. She may have all the talents in the world but not having the courage to go up in the stage will not serve her best interest. Her inability to tolerate her fears made her it maladaptive.