Throughout modern history, genocide has often reared its ugly head. And while the broad strokes of the Holocaust have found their way into history textbooks, our greatest reminder to 'never forget' remains with its survivors and their stories. Thanks to Brad Zarlin, nearly 2,000 survivors have their stories recorded and publicly available, so we can never forget the atrocities they experienced. He shares how he became a prolific Holocaust survivor archivist and the stories he learned along the way.