History of C

  • Developed by Brian Kernighan and Dennis Ritchie of AT&T Bell Labs in 1972
  • In 1983 the American National Standards Institute began the standardisation process
  • In 1989 the International Standards Organisation continued the standardisation process
  • In 1990 a standard was finalised, known simply as “Standard C”
  • Everything before this is known as “K&R C. 


C was invented primarily by Brian Kernighan and Dennis Ritchie working at AT&T Bell Labs in the United States. So the story goes, they used to play an “asteroids” game on the company mainframe. Unfortunately the performance of the machine left a lot to be desired. With the power of a 386 and around 100 users, they found they did not have sufficient control over the “spaceship”. They were usually destroyed quickly by passing asteroids.

Taking this rather personally, they decided to re-implement the game on a DEC PDP-7 which was sitting idle in the office. Unfortunately this PDP-7 had no
operating system. Thus they set about writing one.

The operating system became a larger project than the asteroids game. Some time later they decided to port it to a DEC PDP-1 1. This was a mammoth task, since everything was hand-crafted in assembler.

The decision was made to re-code the operating system in a high level language, so it would be more portable between different types of machines. All that would be necessary would be to implement a compiler on each new machine, then compile the operating system.

The language that was chosen was to be a variant of another language in use at the time, called B.


B is a word oriented language ideally suited to the PDP-7. but its facilities were not powerful enough to take advantage of the PDP-1 1 instruction set. Thus a new language, C, was invented.