Jun 1, 2014

C Programming #02: A Brief history of C

You will appreciate a particular subject if you dwell into history of it.  It helps you developing fondness to it. This article will touch upon brief history of C.

C was developed by Dennis Ritchie between 1969 and 1973 at AT&T Bell Labs.

Unix and C - a great friends

The origin of C is closely tied to the development of the Unix operating system. C was originally developed in assembly language on PDP-7 by Dennis Ritchie and Ken Thompson. Later it was ported to better machine called PDP-11. By 1972 part of Unix was written in C. Slowly even the Unix kernel was written in C. Unix was one of the first operating system kernel implemented in a language other than assembly. Hence development in Unix has helped C to evolve.

C - what is in the name ?

The language was named "C" because its features were derived from "B" programming language. According to Ken Thompson "C" was a stripped-down version of the BCPL programming language. (BPCL was derived from B) It is simple yet complex at times, it is as deep as Sea.

K and R C

In 1978 first edition of "The C Programming Language" was published. It was written by Dennis Ritchie and Ken Thompson creators of C. It became a defacto informal standard of C and people started calling it as K and R C. Later C was standardized with necessary changes by ANSI.


In 1989 ANSI came with the C Standard based on K and R C and its Unix implementation based on it. Hence this standard is referred to as ANSI C, Standard C or C89 standard. Later in 1990 it was accepted by ISO, which is referred to as C90.  But basically C89 and C90 are referring to same standard. Later in 1999 it was further revised and it came to know as C99 standard. Latest one is C11 as you might have guessed it was published in 2011.

Details of standard and difference between standard are not touched upon as of now.You just need to know as of now that there are different standards, of which C99 is most accepted. Differences and new concepts in standards will be covered topics wise.


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