hook_form_node_type_form_alter does not work The sort comments module has a  function in sort_comments.module as below:

  /* drupal@ganovelli.it - blackice78 */
  define('SORT_COMMENTS_OLDER_FIRST', 1); // default
  define('SORT_COMMENTS_NEWER_FIRST', 2);
   /* Alter node type form: allow user to decide comments sorting */
 function sort_comments_form_node_type_form_alter(&amp;$form, $form_state) {
  $form['comment']['comment_default_sorting'] = array(
 '#title' =&gt; t('Sort'),
 '#type' =&gt; 'select',
 '#options' =&gt; array(1 =&gt; t('Older first'), 
                     2 =&gt; t('Newer first')),
 '#default_value' =&gt; variable_get('comment_default_sorting_' . $form['#node_type']-  &gt;type, SORT_COMMENTS_OLDER_FIRST), 
  );
 }


so that if you go to structure>content types, and for example for Article choose edit, then in comment setting, it will give you a drop down menu, so that you can select the order for showing comments, older first or newer first. 

I am trying to do something similar, so in order to see how does it work, I have this in my annotations.module file:

define('Annotations_OLDER_FIRST', 1); // default
define('Annotations_NEWER_FIRST', 2);
/* Alter node type form: allow user to decide comments sorting */
function Annotations_form_node_type_form_alter(&amp;$form, $form_state) {
  $form['comment']['annotations'] = array(
    '#title' =&gt; t('Sort'),
     '#type' =&gt; 'select',
    '#options' =&gt; array(1 =&gt; t('Older first'), 
                     2 =&gt; t('Paragraph number')),

  #default_value' =&gt; variable_get('annotations_' . $form['#node_type']-  &gt;type, Annotatiios_OLDER_FIRST), 
  );
  }


But I can not see the drop down menu, at the same place that I see the drop down menu for sort comments module. Does anybody know what is the reason?
You have a syntax error on the last line, it should start with an apostrophe, and your constant is mispelled.  So it probably isn't compiling properly.  If drupal was picking up the hook you would probably get a white screen of death.

So this means:

You need to make sure the beginning of the function name is exactly the same as your module name - did you use a capital A when naming the module?  PHP is case sensitive.

Lastly, make sure you clear the cache so that Drupal picks up the new hook.  Install drush if you haven't already, go to the /install_directory/sites/mysite directory and run

drush cc all


(assuming you're on linux with command line access)