As we discussed earlier in the introduction part itself that, C Program is a high level programming language which was invented by Dennis Ritchie in AT&T Bell labs, and it was developed between 1969 and 1973. Before the development of C, there was another language, which is known as 'B', which was also developed by Dennis Ritchie. Although 'B' doesn't exists anymore now, C has extracted several features from 'B' and thus the name 'C' came for the new language.
Development of C :
The development of the UNIX operating system language in PDP-7 series microcomputers gave several ideas for the development of C for Ritchie and Thompson. When they decided to develop a new operating system for the PDP-11, they found that, B's features were not compatible with PDP-11. The byte addressability with the PDP-11 was the major issue with the 'B'. So this encouraged them to go for a new programming language for an operating system for PDP-11. C was also intended to develop UNIX itself.
When C was developed, it was only implemented in UNIX operating systems, by Ritchie and Thompson. But, when IBM-PC proposed to implement C in their systems, C was found compatible with their system which made C as a popular programming language of all time.
In 1983, ANSI (American National Standards Institution) established a committee to provide some standard specifications to C, and it was sanctioned as ANSI X3 159-1989, which was also known as C89. And in 1990, the specification was again altered by ISO (International Organization of Standardization) and named as C90.
According to Ritchie, after the development of UNIX in C, There was a two improved features that made C a better language than before.
Portability
Installation of UNIX to newly developed computers was made much easier, than before, because, C reduced the risk of translating the entire operating system to the assembly language.
Improvability
Implementation of C in UNIX operating system made UNIX easy to customize and can be improved by any programmer who could learn the high-level C programming language. Many did learn C, and went on to conduct several experiments by modifying the operating system itself and were able to produce new features and improvements.