Serial killers are the individuals who commit a series of murders, killing three or more people with the murders taking place over more than a month and including a significant break between them. The murders are usually committed as separate events. Serial killers derive abnormal psychological gratification from torturing and killing people and most serial killings involve sexual contact with the victim. They may exhibit varying degrees of mental illness and/or psychopathy, which may contribute to their homicidal behavior. American criminal H. H. Holmes was one of the first documented serial killers in the modern sense of the term, and was believed to have killed more than 200 victims in the late 19th century. Coming to the 20th century, Ted Bundy is believed to be one of the most evil and enigmatic serial killers ever convicted. Well educated, intelligent, and good looking, he terrorized people for four years over the course of which he killed 35–36 women. Columbian Luis Alfredo Garavito Cubillos and Brazilian Pedro Rodrigues Filho are believed to have claimed over a 100 victims each. While a majority of serial killers are male, history has also seen some vicious female serial killers like Elizabeth Báthory and Aileen Wuornos. This section provides you information about the life and crimes of various notorious serial killers from all over the world.