The C Programming Language in the context of Dennis Ritchie

In computing, source code, or simply code or source, is human readable plain text that can eventually result in controlling the behavior of a computer. In order to control a computer, it must be processed by a computer program – either executed directly via an interpreter or translated into a more computer-consumable form such as via a compiler. Sometimes, code is compiled directly to machine code so that it can be run in the native language of the computer without further processing. But, many modern environments involve compiling to an intermediate representation such as bytecode that can either run via an interpreter or be compiled on-demand to machine code via just-in-time compilation.

C is a general-purpose programming language. It was created in the 1970s by Dennis Ritchie and remains widely used and influential. By design, C gives the programmer relatively direct access to the features of the typical CPU architecture, customized for the target instruction set. It has been and continues to be used to implement operating systems (especially kernels), device drivers, and protocol stacks, but its use in application software has been decreasing. C is used on computers that range from the largest supercomputers to the smallest microcontrollers and embedded systems.

A successor to the programming language B, C was originally developed at Bell Labs by Ritchie between 1972 and 1973 to construct utilities running on Unix. It was applied to re-implementing the kernel of the Unix operating system. During the 1980s, C gradually gained popularity. It has become one of the most widely used programming languages, with C compilers available for practically all modern computer architectures and operating systems. The book The C Programming Language, co-authored by the original language designer, served for many years as the de facto standard for the language. C has been standardized since 1989 by the American National Standards Institute (ANSI) and, subsequently, jointly by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC).

Brian Wilson Kernighan (/ˈkɜːrnɪhæn/; born 30 January 1942) is a Canadian computer scientist.He worked at Bell Labs and contributed to the development of Unix alongside Unix creators Ken Thompson and Dennis Ritchie. Kernighan's name became widely known through co-authorship of the first book on the C programming language (The C Programming Language) with Dennis Ritchie. Kernighan affirmed that he had no part in the design of the C language ("it's entirely Dennis Ritchie's work").

Kernighan authored many Unix programs, including ditroff. He is coauthor of the AWK and AMPL programming languages. The "K" of K&R C and of AWK both stand for "Kernighan".