Unique to humans, happiness is one of the hardest emotions to define or understand. What do we really know about the science of happiness?

Cold War spies, Aztec conquerers and Roman senators — history shows anyone could be a traitor.

Forced to work for the notorious Dr. Josef Mengele at Auschwitz, Gisella Perl risked all to save as many lives as she could. This is her incredible, heartbreaking story.

Who's to say that horror should only be consumed by adults? These scary stories for kids will make you want to sleep with the light on.

Discover one of the weirder theories to be made about what the heart can do in this examination of organ transplant memories.

Not even two months after Lincoln's 56th birthday, he was shot dead. Those near the president in his last moments suffered some pretty eerie fates.

Most people know who Rosa Parks is — here are four other women in the Civil Rights Movement whose names you should know.

Will one of these theories prove Steven Avery's innocence?

In the U.S. alone, the vibrator is a billion dollar industry. But how long have they really been around, and who invented them?

Sometimes, the U.S. is on the receiving end of declarations of war.

Where did our current funeral rituals come from, and as they fall out of fashion, what will we replace them with?