Drupal Hello World

helloworld.info

name = Hello World
description = "The most basic exercise known to programmers, the good old Hello world."
core = 7.x

helloworld.module

<?php

/**
 * @file
 * Hello world module.
 */

/**
 * Implements hook_menu().
 */
function helloworld_menu() {
  $items['hello-world'] = array(
    'title' => 'Hi',
    'page callback' => 'helloworld_say_hi',
    'access callback' => TRUE,
  );
  return $items;
}

/**
 * Page callback to say hi to the world.
 */
function helloworld_say_hi() {
  return array('#markup' => 'Hello World');
}