Phobias are very common, in fact most people will have a specific fear about something, like spiders. It is only when this fear has a significant impact on a person’s life that it is really thought of as a phobia.
A phobia is a type of anxiety disorder. It is an excessive fear about a thing or situation that is not logical. So rather than a false alarm it is an excessive response to something that may be fearful for some people. With a phobia a person will arrange their lives to avoid coming into contact with the feared thing or situation.
Phobias are often about animals, natural things (such as heights or water), having an injection or seeing blood (called blood-injection-injury phobia) or a situation (like being on a plane or in an enclosed space). Specific fears are very common in children and many, like separation anxiety disorder, are are normal part of child development. Fears that follow a normal childhood development pathway are not considered to be a sign of an anxiety disorder.
Phobias can lead to panic attacks but these are different to those seen in panic disorder. With panic attacks due to a phobia the panic is triggered by the specific thing the person has a phobia about. So the the panic attack is predictable and specific to a certain context.
Some phobias, such as Hippophobia (the fear of horses) will probably only have a mild impact on a person’s life because the feared object or situation is not part of daily life (and easy to avoid if needed). Other phobias, such as Amaxophobia (the fear of riding in cars) can have a significant impact on a person’s quality of life because they are either an important part of daily life or hard to avoid. For others a phobia may be so strong that even though it may not be essential to day-to-day life it still impacts their quality of life. When quality of life becomes an issue professional help from a psychologist can improve day-to-day living.