Dennis Ritchie
Co-creator of Unix and C programming language
Dennis MacAlistair Ritchie (September 9, 1941 – c. October 12, 2011) was an American computer scientist. He created, together with long-time colleague Ken Thompson, the Unix operating system and the C programming language. Born in Bronxville, New York, Ritchie moved as a child to Summit, New Jersey, where he graduated from high school. He earned degrees in physics and applied mathematics from Harvard University in 1963. In 1967, he joined Bell Labs’ Computing Science Research Center. While at Harvard, he completed a draft of a PhD thesis on computational complexity under Patrick C. Fischer, but he never officially received the degree; a lost copy was later recovered by the Computer History Museum. At Bell Labs, Ritchie and Thompson worked on the Multics operating system before Thompson developed a new system on a PDP-7 machine, with Ritchie’s help. Brian Kernighan coined the name “Unix” as a pun on “Multics.” Thompson created the B programming language for system-level work, which Ritchie then replaced with C. Ritchie continued to refine both Unix and C for many years. In the 1970s, he collaborated with James Reeds and Robert Morris on a ciphertext-only attack against the M-209 cipher machine, but after discussions with the National Security Agency, they withheld publication because the technique applied to machines still used by foreign governments. Ritchie also contributed to the Plan 9 and Inferno operating systems and the Limbo programming language. He was transferred to Lucent Technologies during an AT&T restructuring in the mid-1990s and retired in 2007 as head of System Software Research. With Brian Kernighan, Ritchie co-wrote *The C Programming Language*, often called K&R. His C language became widely used in application, operating system, and embedded development, influencing languages such as C++, Objective-C, C#, and Java. Ritchie and Thompson received the 1983 Turing Award, the 1990 IEEE Richard W. Hamming Medal, and the 1998 National Medal of Technology. In 2011, they were awarded the Japan Prize for Information and Communications. Ritchie was found dead at his home in Berkeley Heights, New Jersey, on October 12, 2011, at age 70.
- born
- September 9, 1941, Bronxville, New York
- died
- c. October 12, 2011, Berkeley Heights, New Jersey
- field
- Computer science
- nationality
- American
- known_for
- Co-creator of Unix operating system, creator of C programming language, co-creator of B programming language
Lore & Background
Ritchie was born in Bronxville, New York. His father was Alistair E. Ritchie, a longtime Bell Labs scientist and co-author of The Design of Switching Circuits. As a child, Dennis moved with his family to Summit, New Jersey, where he graduated from Summit High School. He graduated from Harvard University with degrees in physics and applied mathematics in 1963. In 1967, Ritchie began working at the Bell Labs Computing Science Research Center. In 1968, he completed a draft of his PhD thesis on 'Computational Complexity and Program Structure' at Harvard under Patrick C. Fischer, but never officially received his PhD degree. During the 1960s, Ritchie and Ken Thompson worked on the Multics operating system at Bell Labs. Thompson found an old PDP-7 machine and developed his own application programs and operating system from scratch, aided by Ritchie and others. In 1970, Brian Kernighan suggested the name 'Unix'. Thompson created B; later, B was replaced by C, created by Ritchie. During the 1970s, Ritchie collaborated with James Reeds and Robert Morris on a ciphertext-only attack on the M-209 US cipher machine. Ritchie was also involved with the development of Plan 9, Inferno, and the programming language Limbo. As part of an AT&T restructuring in the mid-1990s, Ritchie was transferred to Lucent Technologies, where he retired in 2007 as head of System Software Research Department.
Reader's Guide
Ritchie created the C programming language and was one of the developers of the Unix operating system. With Brian Kernighan, he co-wrote The C Programming Language. Ritchie worked together with Ken Thompson, who is credited with writing the original version of Unix; one of Ritchie's contributions to Unix was its porting to different machines and platforms. C is widely used in application, operating system, and embedded system development. C influenced C++, Objective-C, C#, and Java. Ritchie and Thompson used C to write Unix. In a 1999 interview, Ritchie clarified that he saw Linux and BSD as derivatives of Unix.
Did You Know?
- Ritchie never officially received his PhD degree, though a draft of his thesis was found in 2020.
- The name 'Unix' was suggested by Brian Kernighan in 1970 as a pun on 'Multics'.
- Ritchie and Thompson received the Turing Award in 1983 for their development of the UNIX operating system.
- Ritchie was found dead on October 12, 2011, at his home in Berkeley Heights, New Jersey.
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
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