A serial killer is a person who murders three or more people, usually doing so for abnormal psychological gratification, thrill-seeking, attention, or financial gain. The definition of a serial killer differs between authorities where the period is changed or the number of murders. The FBI defines a serial killer as committing two or more murders as separate events and usually done by one person acting alone.
Serial killings are often attempted similarly, and victims often have something in common, such as similar demographic profiles. Ted Bundy, for example, targeted attractive, college-aged females. Serial killers have some common characteristics among them, such as varying degrees of psychopathy, a history of abuse by a family member, may have a fascination with setting fires, or are involved in sadistic activities such as torturing animals.
The United States had more serial killers than any other country. California has the highest number of serial killings with 1,628 total, followed by Texas with a total of 893. Alaska has the highest rate of serial killings at 7.01 per 100,000. All 50 states have had a notorious serial killer, such as Florida's Ted Bundy, Illinois's John Wayne Gacy, and New Jersey's Charles Edmund Cullen. Below is a table of each state's serial killings and the rate of serial killings.