Occasional anxiety is an expected part of life. You might feel anxious when faced with a problem at work, before taking a test, or before making an important decision. But anxiety disorders involve more than temporary worry or fear. For a person with an anxiety disorder, the anxiety does not go away and can get worse over time. The symptoms can interfere with daily activities such as job performance and relationships.
There are several types of anxiety disorders, including generalized anxiety disorder, panic disorder, post-traumatic stress disorder (PTSD), various phobia-related disorders.
Source: NIMH
