Wolfenstein 3D is a first-person shooter video game developed by id Software and published by Apogee Software. Originally released on May 5, 1992, for the PC operating system DOS, the game was inspired by the 1980s Muse Software video games Castle Wolfenstein and Beyond Castle Wolfenstein. A promotional version of Wolfenstein 3D was released as shareware, which permitted it to be copied widely. The game was later ported to a wide range of computer systems and video game consoles.