C Introduction

C icon

What is C?

C is a general-purpose and procedural computer programming language. It has been around for nearly 50 years. Dennis Ritchie developed C language at AT & T Bell Labs, the USA between 1969 and 1973. C is the most used programming language.

The main features of C Language include low-level access to memory, a simple set of keywords, and clean style, these features make C language suitable for system programming for example an operating system or compiler development.

Many later languages have borrowed syntax/features directly or indirectly from C language. Languages like Java, PHP, Perl, JavaScript, and many other languages have their syntax heavily based on C language. C++ is nearly a superset of C language(There are few programs that may complie in C but not in C++).

C Language was invented to develop to write an operating system called UNIX. It was originally first implemented on the DEC PDP-11 computer in 1972. In 1978, Brian Kernighan and Dennis Ritchie produced the first publicly available description of C, now known as the K&R standard.

C has now become a widely used professional language for various reasons :-

  • C language is easy to learn.
  • Structured language.
  • Produces efficient programs.
  • Can handle low-level activities.
  • Compiled on variety of Computer platfroms.

Facts about C Language:

  • C is a successor of B language which was introduced in early 1970’s.
  • The UNIX OS was totally written in C.
  • In 1988 C was formalized by American National Standard Institute(ANSI).
  • Most of the state-of-the-art software have been implemented using C.
  • Today’s most popular Linux OS and RDBMS MySQL is written in it.

Why use C ?

C was initially used for system development work , programs that make up the operating system. C was adopted as a system development language because it produces code that runs as fast as the code written in assembly language.

Some examples of used C in that area might be:

  • Operating Systems
  • Language Compilers
  • Assemblers
  • Text Editors
  • Print Spoolers
  • Network Drivers
  • Modern Programs
  • Databases
  • Language Interpreters
  • Utilities

C Programs

A program in C can vary from 3 lines to millions of lines. But First of all, you will need a text editor to write your code. You can use “vi” or “vim“, “notepad“, “sublime text” or any other text editor to write your C program and save it with a “.c” extension, for example, hello_world.c. You will also need a C compiler that will convert your program written in human-readable form into machine language so that your CPU can actually understand and execute your program as per the instructions are given. The most frequently used and free available compiler is the GNU C/C++ compiler, otherwise, you can use the different compiler as per your requirements. Nowadays you can use online compilers for learning basics of C there are lots of websites the service like online language compilers, interpreters.

Example of C Program

#include <stdio.h>
 int main(){
  printf("Hello, World!");
  return 0;


Hello, World!