| Author Name | Profession | Nationality |
| Oded Fehr | Actor | Israeli |
| Odysseas Elytis | Writer | Greek |
| Oksana Baiul | Athlete | American |
| Olafur Eliasson | Artist | Danish |
| Oliver Evans | Inventor | American |
| Oliver Hardy | Actor | American |
| Oliver Kahn | Athlete | German |
| Oliver St. John | Statesman | English |
| Olivia De Havilland | Actress | American |
| Omar Epps | Actor | American |
| Omar Khayyam | Poet | |
| Oriana Fallaci | Journalist | Italian |
| Orlando A. Battista | ||
| Orlando Cepeda | ||
| Orlando Gibbons | Composer | English |
| Orlando Jones | Comedian | American |
| Orrin Hatch | Politician | |
| Orson Scott Card | Writer | American |
| Osama Bin Laden | Criminal | |
| Osbert Lancaster | Cartoonist | English |
| Oscar Hammerstein | Writer | American |
| Oscar Hammerstein Ii | Musician | American |
| Ossie Davis | Actor | American |
| Otto Bauer | Writer | Austrian |
| Otto Hahn | Scientist | German |
| Otto Hermann Kahn | Businessman | German |
| Otylia Jedrzejczak | Athlete | Greek |
| Owen Feltham | Author | British |
| Owen Glendower | Royalty | Welsh |
| Owen Hart | Entertainer | Canadian |
“Making this movie was a great opportunity for me to explore high-definition. I'm glad I got to see what the challenges are, what makes it better. It works wonderfully.”
“You know, what 'New Girl' is doing is they're bringing in really cool people. These are home-run people who aren't your typical guest-star-type people.”