Keywords And First Program Hello World in C Programming.

In C programming language, there are some words stored on its compiler library. These words have performed some task or instruction which was already written on it. These types of words are known as Keywords.

You cannot define a variable which name is exactly matching with keywords. Because if you create them they perform their instruction rather than yours. Keywords are also known as ‘Reserved Words’.

In c programming, you can also create your keyword as well. There are only 32 keywords available in c programming.

Hello World – The first C Program

Friends, So far we have learned about variable, constant, and keywords. Let combine all of these to form a simple program in C language.

Let now write down our first c program. In this program, we are going to print a simple “Hello World!!” which is displayed on your monitor screen.  Let’s begin…


/* Welcome to Mad About Computer */
#include <stdio.h>
printf("Hello World!!");
return 0;


Now, look at the function of all the above code.

1. The First line in the program #include <stdio.h> is preprocessor command, which tells the compiler to include the content of <stdio.h> file in the program. The full form of stdio.h is Standard Input and Output. Stdio.h is a header file(Extension of the header file is .h) which contains functions such as Printf() or Scanf() to take input from the user and display the Output respectively.

2. The Next line main() is the main function where the program execution starts.

3. The Next line is printf(“…”). It is a function which comes under the <stdio.h> header file to display the several lines which you write in it as Output. (write you messages under the double comma otherwise it can’t display )

4. And the last line of the program returns 0. It describes that return 0; terminate the int main() function and the program return value in 0.

In this tutorial, we learn about keywords in c programming language and first c program called Hello World. If you find any mistakes on it. Or if you have any quarry related to it please comment below. Follow us for more programming tutorials.

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