Insomnia is also known as sleeplessness, is a sleep disorder where people have trouble sleeping. In this paper, there is a detailed description of different types of insomnia. The causes of sleeplessness are mentioned. Various signs and symptoms of this disorder are discussed. There is a focus on the diagnosis of the sleep disorder. Risk factors of insomnia are described. The main aim of this paper is to explain the medical and other alternative treatments of insomnia and how someone can prevent from this disorder.