As an undergraduate, Cohen studied Physics at Harvard University. While attending the universtiy, he also wrote for the Harvard Lampoon, a student humour magazine famous for cultivating the talent of many young comedy writers. Cohen also pursued graduate study in Computer Science at the University of California, Berkeley.
Cohen spent several years working as a writer for the Simpsons. He is credited as the writer of the following episodes:
- Lisa the Vegetarian (Season 7)
- Much Apu About Nothing (Season 7)
- The Itchy & Scratchy & Poochie Show (Season 8)
- Lisa the Skeptic (Season 9)
- Das Bus (Season 9)
- Bart the Mother (Season 10)
He was also a co-writer for several other episodes:
- Treehouse of Horror V (Season 6)
- Treehouse of Horror VI (Season 7)
- 22 Short Films About Springfield (Season 7)
- Treehouse of Horror VII (Season 8)
- The Simpsons Spin-Off Showcase (Season 8)
- Treehouse of Horror VIII (Season 9)
- Treehouse of Horror IX (Season 10)
Cohen is also fairly well known for coming up with the word cromulent (meaning acceptable), which appeared in the season 7 episode of the Simpsons: ‘Lisa the Iconoclast.'
In 1997, Cohen teamed up with the Simpsons creator Matt Groening to develop the science fiction animated show, Futurama. The show first aired in 1999 to moderate success. However, due to a declining number of viewers, the show was cancelled in its fourth season.
After successful DVD sales and popular re-runs, Comedy Central signed up to air 16 new episodes, which would eventually be brought out as 4 direct-to-DVD movies. Following the success of these
, Comedy Central signed up for a further 26 new episodes that are scheduled to air sometime in 2010.
Since the show's inception, Cohen has served as head writer end executive producer. He has been credited as writer for the following episodes.
- Xmas Story (Season 2)
- The Why of Fry (Season 4)
Cohen also co-wrote several episodes and direct-to-DVD movies:
- Space Pilot 3000 (Season 1)
- Anthology of Interest I (Season 2)
- Anthology of Interest II (Season 3)
- Rebirth (Season 6)
- Benders Big Score
- The Beast with a Billion Backs
- Bender's Game
- Into the Wild Green Yonder
Cohen changed his middle initial from S to X in 1998 under instruction from the Writers Guild of America, who insisted that no two members should have the same name.