Serial killers are often characterized by a lack of empathy and remorse for their victims.

Jack the Ripper, active in London in the late 19th century, is often regarded as the first modern serial killer due to the widespread media attention and public fascination surrounding his crimes.

Hannibal Lecter, a brilliant psychiatrist and cannibalistic serial killer, is known for his calculated and methodical approach to his crimes, often leaving behind minimal evidence.

Sadism is a psychological disorder characterized by the enjoyment of inflicting pain or suffering on others, which can be a motivating factor for serial killers.

John Wayne Gacy, also known as the "Killer Clown," targeted young boys and often lured them with candy or the promise of a job.

Spree killing refers to the rapid and sequential killing of multiple victims in a short period of time, typically within a few hours or days.

Richard Ramirez, also known as the "Night Stalker," targeted and murdered women in the Los Angeles area during the 1980s.

Compulsive killing refers to the psychological state in which a serial killer feels an overwhelming urge or need to kill in order to satisfy an inner compulsion.

Ted Bundy targeted and murdered young women in the Pacific Northwest during the 1970s and 1980s.

Mass murder refers to the killing of multiple victims in a single event, typically involving four or more victims.

Jeffrey Dahmer targeted and murdered young men and boys in the Milwaukee area during the 1990s.

Sexual sadism refers to the psychological state in which a serial killer derives sexual pleasure from inflicting pain or suffering on others.

Andrei Chikatilo targeted and murdered young women in the Rostov Oblast region of Russia during the 1980s and 1990s.

Serial killing refers to the behavior of a serial killer who kills multiple victims over an extended period of time, often with a specific modus operandi or pattern.

Peter Sutcliffe, also known as the "Yorkshire Ripper," targeted and murdered young women in the Yorkshire area of England during the 1970s and 1980s.