Creating a Program in C Language

There are some rules for writing a program in C language and before writing the program you should have the knowledge of all the rules. Here are the rules you need to follow.

  • Each of the instruction in the C program is written in the separate statement. So we can say that a C program would be composed of a series of statements.
  • All the statement in the program should appear in the same order in which we want them to be executed unless the logic of the problem requires a jump or transfer of the control to a statement which is out of sequence.
  • You can insert blank spaces between two words to enhance the readability of the statement. However you can not add blank spaces within a variable, constant or keyword.
  • All of the statements needs to be entered in small case letters.
  • C language has got no specific rules for the position at which the statement needs to be written, therefore it is known as a free-form language.
  • Each C statement needs to be ended with a ; so ; acts as a statement eliminator.

Here is an example of C language program

/* Calculation of simple interest */

/* Author gekay Date: 5/10/2020 */

main( )


int p, n ;

float r, si ;

p = 1000 ;

n = 3 ;

r = 8.5 ;

/* formula for simple interest */

si = p * n * r / 100 ;

printf ( “%f” , si ) ;


Here are few tips about the above mentioned program

  • The comments about the program needs to be enclosed within /* */. like the first two statements in our program are comments.
  • Comments are not necessary but it is advisable to add comments in your program indicating the purpose of the program.
  • You can add any number of comments in the program and at any place like you can add comment before the statement, after the statement or within the statement.
  • In /* .. */ normal rules of the language do not apply therefore you can type the text in any case or combination.
  • A comment can be split over more than one line like

/* This is

a test

program */