Why do so many of us have the need to be trendy, to do or say things we think make us look as cool as the people we’re copying? Trends through the ages have included everything from style statements to full-on body modification.

The Backstory: The Horrifying Afterlife of Lincoln's Guests at Ford's Theater
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The Backstory: The Secret NASA Test That Almost Ended the Space Race
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The Backstory: Space Junk Falling From the Sky
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