Phobias are not regular fears or short bouts of anxiety one feels in a stressful situation. They are a type of anxiety disorder that cause acute distress. There are 5 broad categories of phobias - Natural Environment, Animals, Medical, Situations, and Other. While the first four are fairly common, like a fear of thunderstorms, spiders, blood and crowds, the last category is the fear of something as mundane as dirt or even technology! There is even a phobia of phobias! Phobias can be the result of a negative experience or even genetics and learned behavior, and it can even affect one's ability to function. Here are a few common and some not-so-common phobias.