Dennis Ritchie

Lore & Background

Dennis Ritchie was born in Bronxville, New York, to Alistair E. Ritchie, a Bell Labs scientist. He moved with his family to Summit, New Jersey, and graduated from Summit High School. He earned degrees in physics and applied mathematics from Harvard University in 1963. In 1967, he began working at Bell Labs Computing Science Research Center. He completed a draft of his PhD thesis in 1968 but never officially received the degree; a copy was later found by the Computer History Museum in 2020.

During the 1960s, Ritchie and Ken Thompson worked on the Multics operating system at Bell Labs. Thompson then developed a new operating system on a PDP-7 machine, aided by Ritchie and others. In 1970, Brian Kernighan suggested the name 'Unix'. Thompson created the B programming language, which Ritchie later replaced with C. Ritchie continued to contribute to Unix and C for many years. He also collaborated on a ciphertext-only attack on the M-209 cipher machine, which was not published after discussions with the National Security Agency.

Ritchie was involved with the development of Plan 9, Inferno, and the Limbo programming language. As part of an AT&T restructuring in the mid-1990s, he was transferred to Lucent Technologies, where he retired in 2007 as head of System Software Research Department. He was found dead on October 12, 2011, at age 70, at his home in Berkeley Heights, New Jersey, after several years of frail health following treatment for prostate cancer and heart disease.

Reader's Guide

Dennis Ritchie's significance stems from his creation of the C programming language and his co-creation of the Unix operating system, both developed with Ken Thompson at Bell Labs. The C language became widely used in application, operating system, and embedded system development, and its influence is seen in most modern programming languages, including C++, Objective-C, C#, and Java. Ritchie and Thompson used C to write Unix, which established many computing concepts and principles adopted widely. In a 1999 interview, Ritchie described Linux and BSD as derivatives of Unix and as continuations of ideas he and Thompson started. He received numerous awards, including the Turing Award in 1983, the IEEE Richard W. Hamming Medal in 1990, the National Medal of Technology in 1999, and the Japan Prize in 2011. After his death, commentators noted that his work underlies nearly all modern computing software. The Fedora 16 Linux distribution and FreeBSD 9.0 were dedicated to his memory, and asteroid 294727 Dennisritchie was named after him.

Did You Know?

• Ritchie never officially received his PhD degree; a copy of his lost dissertation was found by the Computer History Museum in 2020.
• He collaborated on a ciphertext-only attack on the M-209 US cipher machine, which was not published after discussions with the National Security Agency.
• Ritchie co-wrote the book 'The C Programming Language' with Brian Kernighan, often referred to as K&R.
• Asteroid 294727 Dennisritchie was named in his memory in 2012.

Notable Quotes (Wikiquote)

"I am not now, nor have I ever been, a member of the demigodic party." — Dennis Ritchie "USENET : net.unix-wizards (1984-03-13 (retrieved from the archive in Google Groups))." — Dennis Ritchie "[C has] the power of assembly language and the convenience of … assembly language." — Dennis Ritchie "Quoted in Cade Metz, "Dennis Ritchie: The Shoulders Steve Jobs Stood On", Wired, 13 October 2011." — Dennis Ritchie