«O» was the name of an international fetish magazine published in Germany by Peter W. Czernich. It was published both in German and English. The last issue, «O» No. 25, was published in summer 1995. «O» magazine was followed by Marquis magazine.
The name comes from the French sadomasochistic novel Histoire d'O.
The magazine was notably in a trademark fight with Oprah Winfrey and Hearst Magazines over their O, The Oprah Magazine title.