O addressed high school and college graduates across the U.S. Friday as part of Facebook's plan to honor graduating students in lieu of physical ceremonies, which have been canceled due to the COVID-19 pandemic.

Oprah acknowledged this is not the graduation any of them envisioned but said that's what makes them special ... heading into a real-world filled with even more uncertainty than usual.

She tells them ... "Never has a graduating class been called to step into the future with more purpose, vision, passion and energy and hope."

Friday's event was hosted by Mindy Kaling and B.J. Novak and also featured appearances by DJ Khaled, Cardi B, Awkwafina, Lil Nas X, John Mayer, Matthew McConaughey, Miley Cyrus and many more.

Oprah's inspirational for sure. If we can offer a few words of our own ... with every crisis comes opportunity. There will be new ways of living, conducting business and socializing. For graduates who had plans that were torpedoed by the virus, figure out where there's a hole in the marketplace -- where you can provide a service of value. The reality in crisis ... ingenuity usually rules.

Barack Obama's slated to speak Saturday, and it all leads up to National Graduation Day on May 17.