Sixteen million viewers in the United States alone tuned in for The Oprah Winfrey Show finale. In the historic final hour, Oprah took the stage as teacher in the world's biggest classroom, highlighting the principles that guide her life, many of which were gleaned from the 4,561 hours of The Oprah Winfrey Show. In an all-new series, "Oprah's Lifeclass", Oprah reaches back through the show's 25-year history to teach the lessons that matter most to her...the guidelines for fulfilling your life's potential, breaking through your barriers, understanding your purpose, letting go of anger, how to use joy to fuel your life and becoming all you were meant to be. It is the ultimate life class. Oprah will share her most personal revelations and what she thinks now about those iconic show moments and guests. (Source: OWN)