An unmanned U.S. Predator drone flies over Kandahar Air Field in Afghanistan in 2010. Apple has rejected an app that tracks U.S. drone strikes around the world. Kirsty Wigglesworth/AP hide caption

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President Obama posted this photo on Twitter and Reddit to prove that he was participating in Wednesday's online chat. Some users weren't quite convinced. via Twitter hide caption

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President Obama waves to supporters during a campaign stop Wednesday in Charlottesville, Va. He later participated in a question-and-answer session on Reddit. Alex Wong/Getty Images hide caption

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Students work at the University of the People student computer center in Haiti. Students from 129 countries are currently enrolled with the institution. Courtesy of University of the People hide caption

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Iranian President Mahmoud Ahmadinejad (center) visits the Natanz Uranium Enrichment Facility in April 2008. Israel and the U.S. targeted the facility in 2009 with the Stuxnet cyberattack. AP hide caption

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Generating artificial lightning in Nikola Tesla's laboratory. Bettmann/Corbis hide caption

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Nintendo's Wii U is the only new game system on the horizon as console makers are having a hard time figuring out how to improve on what they've got. Kevork Djansezian/Getty Images hide caption

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