One of the classic computer games, the first-person shooter Wolfenstein 3D, is celebrating its 20th anniversary year with a new browser-based version of the game as well as a promotional giveaway of the iOS version of the original game for a limited time. While the original Castle Wolfenstein first appeared on an Apple II computer in 1981, Wolfenstein 3D (the more familiar version of the game) debuted on DOS in 1992.
