John D. Carmack II (born August 20, 1970) is an American game programmer, and the co-founder of id Software. Carmack was the lead programmer of the id computer games Commander Keen, Wolfenstein 3D, Doom, Quake, and the sequels to Doom, Quake and Wolfenstein.

Though Carmack is best known for his innovations in 3D graphics, he is also a rocketry enthusiast and the founder and lead engineer of Armadillo Aerospace.

Carmack, son of local television news reporter Stan Carmack, grew up in the Kansas City Metropolitan Area where he became interested in computers at an early age. He attended Shawnee Mission East High School in Prairie Village, Kansas and Raytown South High School in nearby Raytown, Missouri. As reported in David Kushner's Masters of Doom, "when Carmack was 14, he broke into a school to steal Apple II computers, was arrested, and sent for psychiatric evaluation (the report mentions "no empathy for other human beings"). Carmack was then sentenced to a year in a juvenile home. ... he was asked "if you had not been caught, would you consider doing it again?" he answered "probably" but when the therapist presented this evaluation he neglected to repeat "if you had not been caught" from his statement". After scoring a 1500 on the SAT (780 Math, 720 Verbal), he attended the University of Missouri–Kansas City for two semesters before withdrawing to work as a freelance programmer.