Insomnia or sleep disorder is a sleep problem faced by people around the world. This disorder is most commonly found in the western countries where the lifestyle is very fast paced.  An essential feature of sleep disorder is dissatisfaction of the sleep. The dissatisfaction is involved with the sleep quantity or quality of sleep. There are different complaints associated with maintaining a good sleep. The most common single symptom of insomnia is the difficulty of maintaining a sleep along with difficulty in falling asleep.