“The C programming language was developed by Dennis Ritchie in Bell Telephone Laboratories, in the early 1970’s. Usage of this language was largely confined to Bell Laboratories until 1978, when Brian Kernighan and Dennis Ritchie described the language in their book “The C Programming Language”. This original form of the C language is referred to as K & RC. The first major use of C language was to write an operating system known as UNIX.”

At the time when programmable computers were available at market commercially, different programming languages were also developed for different purposes. By 1960s, different languages like FORTRAN and COBOL were developed but with specific use and specific purpose. Some of them could be used for scientific work and some of them could be used for business analysis. There was a problem that general purpose programming language was not available. To solve this problem, a committee was set up and a general purpose programming language was developed which was called ALGOL (Algorithmic Oriented Language) in 1960. But the problem with ALGOL was that it was too abstract and too general. So, it could never gain popularity. To solve this problem Cambridge University developed a new programming language in 1963, which was called CPL(Combined Programming Language), which really came its name that it was really the combination of all the programming language available at that time and it was refinement of each of those languages. Again the big problem with CPL was that it was too big, has so many features that it could hardly be learnt by general human mind. Not only hard to learn, but it was hard to implement, so it was again in the same place as that of ALGOL. Again another attempt was made by Martin Richards (at Cambridge University) to solve such problems. He developed a programming language called BCPL in 1967, but it became so less powerful and too much specific. At the same time, many programmers were trying to develop a powerful general purpose programming language; among them Ken Thompson (at AT&T Bell Lab) developed a programming language called B in 1970, but it was too, like other programming languages, much specific and less powerful. B was designed to rewrite UNIX (an operating system written by Ken Thomson) in high level language. Due to weakness in B, primarily lack of structures, this attempt was not successful.

Taking all the good points of BCPL, CPL and B, C programming language was developed in 1972 by Dennis Ritchie at AT&T Bell Lab, USA. Ritchie’s main achievement is the restoration of the lost generality in BCPL and B & still keeping it powerful. C being successor of BCPL, it has all the major advantages of high level programming languages like machine independence and easy to learn and implement. It was concise and provides efficient translator for machine codes. Thompson and Ritchie rewrote UNIX in C.

C was the right language at the time, and has dominated system programming ever since. It is believed that it may dominate the system programming in years to come. Initially the book “The C Programming Language” by Brian Kernighan and Dennis Ritchie served as the standard language reference. A technical subcommittee on C language standardization was formed by the American National Standards Institute (ANSI) in 1982, to purpose a standard definition of C. The standard was finalized in 1989 as American National Standard for Information Systems-Programming language C or just ANSI standard. This book is based on this ANSI standard.