Twitter announced that it has set a price range for its initial public offering between $17 and $20 per share and hopes to sell 70 million shares. Justin Sullivan/Getty Images hide caption

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Reporters watch the final minutes of the presidential debate between President Obama and Republican presidential nominee Mitt Romney last October in Denver. Doug Pensinger/Getty Images hide caption

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This week, several women in the U.K. went public about explicit abuse they received on Twitter. Alastair Grant/AP hide caption

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Weekend Edition Saturday host Scott Simon documented his mother's final days to his more than 1.2 million Twitter followers. Stephen Voss/NPR hide caption

itoggle caption Stephen Voss/NPR