What You Don't Know About How Facebook Uses Your Data
Facebook tracks even nonusers as they surf the web, and House members grilled Mark Zuckerberg, Facebook's chief executive, about the practice during his second day of hearings.
Mark Zuckerberg, Facebook's chief executive, went to Capitol Hill this week to explain to members of Congress how the detailed personal information of up to 87 million Facebook users ended up in the hands of a voter-profiling company called Cambridge Analytica.
What Mr. Zuckerberg got instead, as he testified before the House Energy and Commerce Committee on Wednesday, was a grilling about Facebook's own data-mining practices.