Can the world's most widely accessed collection of information be trusted? And if not, is it possible to change it for the better? In 2001, Jimmy Wales created the first entry on Wikipedia: "Hello world". 20 years later, Wikipedia contains more than 50 million articles with English Wikipedia alone getting more than 300 million clicks per day, and has the professed goal of being free, democratic, and neutral. But is it reliable as a source of factual...