There are a number of habits possessed by individuals that can be classified as nervous habits. These include nail-biting, stammering, sniffling, and banging the head. They are known as symptoms of an emotional state and are generally based upon conditions of anxiety, insecurity, inferiority and tension. These habits are often formed at a young age and may be because of a need for attention. When trying to overcome a nervous habit it is important to resolve the cause of the nervous feeling rather than the symptom which is a habit itself.