The categories are:

Specific phobias: Fear of particular objects or situations that results in anxiety and avoidance. May lead to panic attacks if exposed to feared stimulus or in anticipation of encounter. A specific phobia may be further subdivided into five categories: animal, natural environment, situational, blood-injection-injury, and other. Agoraphobia: a generalized fear of leaving home or a small familiar safe area and of possible panic attacks that might follow. Various specific phobias may also cause it, such as fear of open spaces, social embarrassment (social agoraphobia), fear of contamination (fear of germs, possibly complicated by obsessive–compulsive disorder) or PTSD (post-traumatic stress disorder) related to a trauma that occurred outdoors. Social anxiety disorder (SAD), also known as social phobia, is when the situation is feared out of a worrying about others judging them. Performance only is a subtype of social anxiety disorder Phobias vary in severity among individuals. Some individuals can avoid the subject and experience relatively mild anxiety over that fear. Others experience full-fledged panic attacks with all the associated impairing symptoms. Most individuals understand that their fear is irrational but cannot override their panic response. These individuals often report dizziness, loss of bladder or bowel control, tachypnea, feelings of pain, and shortness of breath. Causes
There are multiple theories about how phobias develop and likely occur due to a combination of environmental and genetic factors. The degree to whether environment or genetic influences have a more significant role varies by condition, with social anxiety disorder and agoraphobia having around a 50% heritability rate.
Traditional systematic desensitization involves a person being exposed to the object they are afraid of over time so that the fear and discomfort do not become overwhelming. This controlled exposure to the anxiety-provoking stimulus is key to the effectiveness of exposure therapy in the treatment of specific phobias. It has been shown that humor is an excellent alternative when traditional systematic desensitization is ineffective. Humor systematic desensitization involves a series of treatment activities that elicit humor with the feared object. Previously learned progressive muscle relaxation procedures can be used as the activities become more difficult. Progressive muscle relaxation helps people relax before and during exposure to the feared stimulus. Virtual reality therapy is another technique that helps phobic people confront a feared object. It uses virtual reality to generate scenes that may not have been possible or ethical in the physical world. It is equally as effective as traditional exposure therapy and offers additional advantages. These include controlling the scenes and having the phobic person endure more exposure than they might handle in reality. Medications
Medications are a treatment option often utilized in combination with CBT or if CBT was not tolerated or effective. Medications can help regulate apprehension and fear of a particular fearful object or situation. There are various medication options available for both social anxiety disorder and agoraphobia. The use of medications for specific phobias, besides the limited role of benzodiazepines, do not currently have established guidelines due to minimal supporting evidence.