C programming uses some syntax and notations that may seem unfamiliar to the people who haven’t programmed computers.
So before you go through the tutorials of C programming, we just begin by writing the first program in C to print a line.
My first program in C: Hello World !!!
Program to display “Hello world!!!”
/* This is my first program in C..*/
#include <stdio.h>
int main()
{
printf("Hello world!!!\n");
return 0;
}
Output
Hello World!!!
Even though the program is simple as it is the first program in c to make you familiar with the programs written in C programming.
It illustrates several important features of C programming language.
Explanation of the Program
Line 1:
The first line of the program begins with /*
and ends with */
which represents that any text written between these two symbols is a comment.
Comments do not affect program while running because C compiler ignores the comments and programmers use these comments for the documentation of the program.
Line 2:
#include <stdio.h>
This is the directive to the C Preprocessor (You might wonder what these words like preprocessor and directives are but don’t worry these things will be crystal clear after going through next chapters).
Lines beginning with #
are called preprocessor directives and this specific line tells preprocessor to include the contents of standard input/output header file ( stdio.h) in the program while the program is being compiled.
Line 3:
int main ( )
This is the main functions of the program which is part of every C program.
C programs can have multiple functions which are also called the building blocks, however, one of the function should be main
.
The code of the function is written between the curly braces and in this program also the body of the function is enclosed by the braces in line 4 and 7.
Line 5:
printf("Hello World!!!");
This is the standard output functions which instruct the computer to print anything written between the quotes (” ..text..”).
This entire line including the printf
, its arguments within the parenthesis and the semicolon is called a statement.
Every statement must end with a semicolon.
Line 6:
return 0;
This is nothing but an exit sequence for the function.
Moreover, it signifies the termination of the function main returning the integer value 0.
Escape sequence in C Programming
Escape sequences are the characters which are not printed. The \
backslash is called escape character.
Escape sequence | Description |
---|---|
\n | Newline. This will place a cursor on the beginning of the second line. |
\t | Tab. This will insert horizontal tab. |
\\ | Backslash. Insert backslash in a string. |
\a | Alert. This will signify alert sign or sound without changing the position of cursor |