Dennis Ritchie, Founder of Unix, C, Dies at 70

Computer scientist Dennis Ritchie, creator of the C programming language and co-developer of the Unix operating system, died Oct. 8 after a long illness.

Dennis Ritchie, creator of the C programming language and co-developer of the Unix operating system, died at home after a long illness. He was 70 years old.

Google engineer and former colleague Rob Pike publicly posted the news on Google+ Oct. 12, writing, "I trust there are people here who will appreciate the reach of his contributions and mourn his passing appropriately." Alcatel-Lucent Bell Labs, where he spent most of his career, issued a statement confirming the news on Oct. 13.

Ritchie was instrumental in the development of the Unix operating system, for which he received the Turing Award in 1983 with co-developer Kenneth Thompson. Ritchie also created C, the second most popular programming language in the world according to TIOBE Software's latest programming language index.

Central to many modern major operating systems and applications, C paved the way for Java and C++. Unix laid the foundation for several future operating systems powering servers, desktops and mobile devices, including BSD which Apple's Mac OS X is based on, and Linus Torvald's Linux, which Google's Android is based on.

"Dennis was well loved by his colleagues at Alcatel-Lucent Bell Labs, and will be greatly missed. He was truly an inspiration to all of us, not just for his many accomplishments, but because of who he was as a friend, an inventor, and a humble and gracious man. We would like to express our deepest sympathies to the Ritchie family, and to all who have been touched in some way by Dennis," Jeong Kim, president of Alcatel-Lucent Bell Labs said in the statement.

Ritchie joined Bell Labs' Computing Sciences Research Center in 1967. As part of AT&T's corporate restructuring in the 1990s, he became part of Lucent Technologies where he remained until 2007. He was the head of the System Software Research Department at Lucent when he retired.

With Unix, Thompson and Ritchie were out to develop an operating system that was portable, efficient and compatible with just about any machine. The duo developed Unix to run on one of the most advanced mini-computers of the time, the Digital Equipment Corporation PDP 11, and released the first edition of the operating system in 1971.

Of Unix, Ritchie is known to have said, "It is very simple, it just needs a genius to understand its simplicity."

Even with its multitasking and multiuser capabilities, the original system had some constraints because it was originally written in assembly language, which meant the program had to be rewritten for each type of hardware. Ritchie and Thompson set out to rewrite Unix in 1973 to make it more flexible, and the C language was born.

Ritchie worked out the syntax and the functionality of the programming language as the team worked on Unix. With the programming language fully fleshed out, Ritchie then co-authored the text "The C Programming Language" in 1978, often considered the definitive work on C.

Ritchie said that C "is quirky, flawed and an enormous success." Programs written in C could be run with little or no modification on any computer that understood the language.

Ritchie's work on Unix was instrumental in the rise of the client-server model as computing moved away from stand-alone machines to networked environments. The architecture's versatility and the ease of adding new tools also made it an attractive platform to use.

Ritchie and Thompson also received the National Medal of Technology in 1998 from President Bill Clinton for their contributions to Unix and C.

Born in Bronxville, N.Y., he graduated from Harvard with a BS in mathematics and a PhD in physics.