From Wikipedia
3D Realms is a standing but not operating publisher and video game developer based in Garland, Texas established in 1987. It is best known for popularizing the shareware distribution model and as the creator of franchises on the PC such as Duke Nukem, and also the publisher of other franchises such as Commander Keen and Wolfenstein 3D.
Unlike traditional larger publishers that sold games in retail outlets, Apogee (like many independent developers) sold their products using the shareware method, depending mostly on BBSs, such as Software Creations, for distribution of their software.
The last game to be published under the Apogee name was Stargunner in 1996. Since 1998, all the company's games have been using a 3D engine. As a result, 3D Realms has replaced Apogee as the brand name to publish games under.
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