Some colleges and police departments are starting to use software that scans social media to identify local threats, but most tips still come from members of the public. Ikon Images/Getty Images hide caption

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Friday, DeMarcus Cousins of the Sacramento Kings reminded sports journalist Clay Travis that his five-year guarantee — that Cousins would be arrested — had expired. Thearon W. Henderson/Getty Images hide caption

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Panelist Nahshon Ellerbe, a star running back at Trinity Christian Academy in Addison, Texas, warms up before a game against Midland Christian. Jeffrey McWhorter/Trinity Christian Academy hide caption

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Social media provides voice to movements and helps drive them. Picking the right platforms for these sensitive conversations, though, is a sign of our growing digital sophistication. iStockphoto hide caption

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Amateur cook and writer Maureen Evans has perfected the art of tweeting a recipe in 140 characters or less. fot. Wojciech Zalewski/iStockphoto hide caption

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The media is all over this story: Ebola in NYC! Don Weiss, a doctor with the New York City Health Department, faces microphones outside the bowling alley visited by the physician who tested positive for the virus. John Minchillo/AP hide caption

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Twitter is suing the federal government over First Amendment rights. The tech company says the government stopped it from releasing extra detail about government requests for user information. iStockphoto hide caption

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