« Index of C                                                               Next Chapter »

History of C

  • C is a programming language developed at “AT & T’s Bell Laboratories” of USA in 1972.
  • Ken Thompson created the B language in 1969 from Martin Richard's BCPL (Basic Combined Programming Language). He used assembly language and B to produce the initial versions of the UNIX operating system. BCPL and B were type less languages in which variables were simply words in memory.
  • Later Dennis Ritchie converted B into C by retaining most of B's syntax in 1972 and wrote the first compiler. This was implemented on DEC's PDP 11 and it was first used as the system's language for rewriting the UNIX operating system.
  • Later on, UNIX, its tools and C grew simultaneously. In 1978, Kernighan and Dennis Ritchie wrote a book entitled 'The C Programming Language' that became the language definition for almost a decade.

Dennis Ritchie

  • C has often been termed as a "Pseudo high level language" or a "Middle level language" by many programmers. This is not because of its lack of programming power but because of its capability to access the system's low level functions.
  • In fact C was invented specifically to implement UNIX. C instructions are compiled to assembly code. Therefore, depending on complexity of the code and on the compiler optimization capabilities, C code may run as fast as assembly.
  • Because C is such a powerful, dominant and supple language, its use quickly spread beyond Bell Labs. In the late 70’s C began to replace widespread well-known languages of that time like PLI, ALGOL etc.
  • Programmers everywhere began using it to write all sorts of programs. Soon, however, different organizations began applying their own versions of C with a subtle difference. This posed a serious problem for system developers. To solve this problem, the American National Standards Institute (ANSI) formed a committee in 1983 to establish a standard definition of C. This committee approved a version of C in 1989 which is known as ANSI C. With few exceptions, every modern C compiler has the ability to adhere to this standard. ANSI C was then approved by the International Standards Organization (ISO) in 1990.
  • The C language is named as its predecessor was called B. The B language was developed by Ken Thompson of Bell Labs.

  « Index of C
                                                               Next Chapter »