Dennis M. Ritchie, Tech Expert Alumnus, Dies At 70

Dennis M. Ritchie ’63, a Harvard graduate who had a profound impact on modern technology, died last week at 70.

Ritchie was the principal designer of the C programming language and co-inventor of the operating system Unix, two inventions that revolutionized modern technology.

The C programming language was widely considered simple and elegant compared to the more cryptic and inaccessible B language that preceded it, and is now widely used. Based on C, Ritchie and Kenneth L. Thompson invented Unix, which is the foundation of today’s predominant operating systems.

Ritchie worked for Bell Laboratories for his entire career.

At Bell, Ritchie met Brian Kerninghan, who became a friend and colleague of 40 years. The two co-authored “The C Programming Language,” a 274-page explanatory book that has been widely translated and sold millions of copies.

“The programming language is the best combination of elegance, expressiveness and efficiency the world has seen. It is hard to overstate the importance of C—any computer or communications system uses C directly or through one of its descendents,” Kerninghan wrote in a letter to USENIX, The Advanced Computing Systems Association.

Ritchie and Thompson received three major awards for their development of Unix. In 1983, the Association for Computing Machinery awarded them the Turning Award. In 1993, President Bill Clinton awarded them the National Medal of Technology and Innovation. And this year, they received the Japan Prize in Information and Communications—which Professor of Physics and of Electrical Engineering Paul Horowitz ’65 called “the Nobel prize of computer science.”

Horowitz, who knew Ritchie from his high school and college years, said that Ritchie and his roommates in Leverett House were “nerdy” but serious about what they did.

“He made a dent in the fabric of computer science,” Horowitz said of Ritchie.

Harvard Professor of Computer Science Harry Lewis blogged about Ritchie’s important contributions.

“Ritchie bears more personal responsibility than anyone else for C and Unix, and hence for their many derivatives. The world would be a VERY different place had he not created these things,” Lewis wrote.

As an undergraduate at Harvard, Ritchie concentrated in Physics. He went on to earn a graduate degree in Applied Mathematics at Harvard’s School of Engineering and Applied Sciences.

Professor of Computer Science Margo L. Seltzer met Ritchie when she was a graduate student.

“It didn’t matter if you were a graduate student or a Nobel Laureate—your thoughts, questions, and opinions mattered just as much as anyone else’s,” she wrote in an email to The Crimson. “From my perspective, Dennis hated being the limelight—he always preferred being treated as ‘just another conference attendee’ and wanted to hang out in the hallway and take part in whatever conversation was going on—it didn’t have to even be about computers.”

“Dennis changed the world and we are all indebted to him,” Kerninghan wrote to USENIX.

Ritchie will be remembered for his quiet, gentle demeanor, Seltzer said.

“He was a wonderful human being—not just a brilliant creator and engineer, but a kind, friendly, witty person,” she said.