According to the book a serial killer kills several victims over a period of time. Almost all serial killers are sociopaths. They lack superego or conscience. A serial killer des not care about the humanity of his victims he does not empathizewith them, or feel remorseful. Serial killers like the power they have over there victims. Most serials killers are driven sexually to kill.
They like the physical contact with there victims. Sociopaths have a character flaw they care about inflicting pain and suffering because as far as they are concerned there victims are unfeeling objects. Killing makes these people feel superior not only to their victims but to the police investigators too. Serial murders have been around for a long time.
The furthest it has been dated back to was in the 1400s. Serial murders are the hardest for police investigators to figure out. Most of the regular murders are done by someone who was close to the victim. Serial murders on the other hand are done at random within a group of people. Police call these stranger killings because neithervictim, nor the victims family knows the killer. This makes it very hard for police to find the killer.
The FBI was able to study many serial killers and have developed a profile to help them catch serial killers. A typical serial killer is a white male that has grown up in a dysfunctional family with an abusive mother. But the most useful physiological insights come from the crime seen itself. The FBI discovered the each criminal mind commits a different signature crime. After over twenty years the FBI has made catching serial killers an art.