#include <stdio.h>
int x;
int main()
{
printf("Hello world \n");
return 0;
}

#include <stdio.h> // Standard C function Library such as printf
int x;             // Declaring the variable x as an integer
int main()        // Entry Point to start the main function
{
printf("Hello world \n");    // This is similar to MATLAB's fprintf
return 0;                    // Outputs a 0, mostly good practive to end
}

#include<iostream>

using namespace std;

int main(){
cout<<"Hello World";
}

int main() {
    std::cout<<"hello world!" << std::endl;
}

main = putStrLn "Hello, world!"
main2 = putStrLn "Hi wo!"

main = putStrLn "Hello, world!"

print("Hello, world!")

print("Hello, world!")

print_endline "Hello, World!"

print_string "Hello, world"

<?php echo "hello world" ?>

<?php 
    echo "Hello World"; 
?>

#!/usr/bin/perl

print("hello world");

#!/usr/bin/perl

print("hello world");

x = 1
print('Hello world!')

greeting = 'Hello World'
print( greeting )

print("Hello World")

module GreetingEn
  def welcome()
    return 'Hello world!'
  end
end

module GreetingKo
  def welcome()
    return '안녕 세계'
  end
end

include GreetingKo
include GreetingEn
puts GreetingKo.welcome()

(display "Hello, World!")

(begin
  (display "Hello, World!")
  (newline))