What are serial killers, and who are the most well-known?

What are serial killers, and who are the most well-known?

Editor’s Note: This story contains discussions of rape or sexual assault that may be disturbing. Reader discretion is advised. If you or someone you know has been sexually assaulted, you can find help and discreet resources on the National Sexual Assault Hotline website or by calling 1-800-656-4673. (NewsNation) — Serial killers have always been a subject of interest. How do their brains work? What motives do they have? And how common are they, …