First off, I would like to explain what the serial killer means. According to Wikipedia, a serial killer is typically a person who murders three or more people, usually in service of abnormal psychological gratification, with the murders taking place over more than a month and including a significant period of time between them. Although it is worth pointing out that different authorities may use different criteria when using the phase. It is necessary to mention that a considerable amount of serial killers fall in the category of psychopaths. A psychopath is different from most people in that they do not feel emotions, such as, among other, any empathy or guilt for there action and the people they may have hurt. They have this in common with sociopaths, but that is one of the few similarities they have.