Before the 20th century, concert musicians might tune their instruments to wildly different pitches, depending on where they were playing.

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Frida Kahlo’s life and work were defined by pain and perseverance. Read on for facts about the accident that changed her life, her famous romances, her exotic pets, and more.
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Tod Browning's sideshow spectacle is considered a classic, or at least a cult favorite, today—but its original reception wasn't quite so welcoming.
Adolf Hitler was not a fan of theirs.
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One technological breakthrough left the common pencil in the dust.
While it was author J.K. Rowling who ultimately suggested the alternative title, she still regrets the decision.
It is one of the most enigmatic stories of all time, with an opening sentence that’s unparalleled in literature. 'The Metamorphosis' is the novel that birthed the adjective 'Kafkaesque.'
On June 30, Flightradar24 broke their record for most flights tracked in a single day.
It's time to play the music, it's time to light the lights ...