Create custom content type from module – Drupal 7

druapl-custom-module.php

<?php
/**

 * hook_install()
 * This will automatically called when a module is installed
 */
function newslettereasy_install() {
   _install_node_type();
}
function _install_node_type() {
  $type = node_type_get_type('easynewsletter');
  if (!$type) {
    $type = node_type_set_defaults(array(
      'type' => 'easynewsletter',
      'name' => t('Easy newsletter'),
      'base' => 'node_content',
      'description' => t('A newsletter issue to be sent to subscribed email addresses.'),
      'locked' => 0,
      'custom' => 1,
      'modified' => 1,
      ));
    node_type_save($type);
    node_add_body_field($type);
  }
  
  variable_set('easynewsletter_content_type_' . $type->type, TRUE);
}