C Hello World Program (Using Functions, Loops, Arrays, and More)

The C language Hello World program is the classic starting point for every beginner learning to code.

In this tutorial, you'll learn various ways to print "HELLO, WORLD!" in C — from basic syntax to variations using loops, arrays, and functions.

Introduction

If you're looking to understand how to write a Hello World Program in C, this guide will help you learn:

• The basic structure of a C program

• How to use printf() to print output

• Different methods to print Hello World using loops, arrays, and functions

Hello World Program in C

// HELLO WORLD PROGRAM IN C USING MAIN FUNCTION
#include <stdio.h>

// It's the main function of the program
int main()
{
    // Step-1 Display a label message
    printf("C HELLO WORLD PROGRAM\n");

    // Step-2 Print the actual Hello World message
    printf("HELLO, WORLD!\n");

    return 0;
}

Run

Output

Using a Function (User-defined)

// HELLO WORLD PROGRAM IN C USING A USER-DEFINED FUNCTION
#include <stdio.h>

// Function to display messages
void showMessage()
{
    printf("C HELLO WORLD PROGRAM\n");
    printf("HELLO, WORLD!\n");
}

int main()
{
    // Call the showMessage() function to print the messages
    showMessage();
    return 0;
}

Run

Using a Loop (For Loop)

// HELLO WORLD PROGRAM IN C USING FOR LOOP
#include <stdio.h>

int main()
{
    // Create a string array of messages
    char *messages[] = {
        "C HELLO WORLD PROGRAM",
        "HELLO, WORLD!"
    };

    // Loop through the array and print each message
    for (int i = 0; i < 2; i++)
    {
        printf("%s\n", messages[i]);
    }

    return 0;
}

Run

Using an Array Only (String Array)

// HELLO WORLD PROGRAM IN C USING STRING ARRAY
#include <stdio.h>

int main()
{
    // Declare an array of strings
    char *msg1 = "C HELLO WORLD PROGRAM";
    char *msg2 = "HELLO, WORLD!";

    // Print both messages
    printf("%s\n", msg1);
    printf("%s\n", msg2);

    return 0;
}

Run

Using Conditional Statements (If statement)

// HELLO WORLD PROGRAM IN C USING IF STATEMENT
#include <stdio.h>

int main()
{
    int showMessage = 1;

    if (showMessage)
    {
        printf("C HELLO WORLD PROGRAM\n");
        printf("HELLO, WORLD!\n");
    }

    return 0;
}

Run

Common Mistakes

• Missing semicolon ; at the end of printf() statements

• Forgetting #include <stdio.h>

• Not returning an integer from main()

FAQs

Q1: Do I always need to use main() in C?
Yes, main() is the entry point of a C program.

Q2: What does printf() do?
It prints output to the standard output (usually the console).

Q3: Can I write C code without functions?
You can write simple code in main() only, but using functions is recommended for cleaner structure.