Year released: 1993
Doom was the game that single-handedly popularized mainstream PC gaming. Sure, there had been a raft of classic games before its release, and Wolfenstein 3D set the template for the FPS one year earlier. However, Doom established concepts that are now core to the PC gaming experience, such as online multiplayer, as well as a highly creative modding community that still exists to this day.
Less salubriously, it also represents, alongside the release of Mortal Kombat in 1992, the birth of the video game violence debate that would lead to the founding of the ESRB. Its upcoming reboot, the first entry in the series since Doom III dropped 10 years ago, recently whipped up a frenzy at Quakecon 2014, making a return to the blisteringly fast gameplay the original is renowned for.