20 years ago John Carmack created its DOOM! A 1993 science fiction horror-themed first-person shooter video game. Its considered to be one of the most significant and influential titles in the video game industry, for having ushered in the popularity of the first-person shooter genre. The popularity of Doom led to the development of expansion packs and alternate versions based on the same game engine, including The Ultimate Doom (1995), Final Doom (1996), and Doom 64 (1997).
