Saving and retrieving value in hook_node_form_alter() This is in Drupal 7.

I have managed to add a section to the node vertical tab. But I have not found out how to save the value and retrieve the value. After saving the node if i go back to the node edit form it still shows the default value. What am I missing?

function myModule_form_node_form_alter(&amp;$form, &amp;$form_state, $form_id) {
  $form['test_settings'] = array(
    '#type' =&gt; 'fieldset', 
    '#title' =&gt; t('test settings'), 
    '#weight' =&gt; 0, 
    '#collapsible' =&gt; TRUE, 
    '#collapsed' =&gt; FALSE,
    '#group' =&gt; 'additional_settings',
   );

   $form['test_settings']['node_uaid'] = array(
    '#type' =&gt; 'textfield',
    '#title' =&gt; t('uaid'),
    '#default_value' =&gt; variable_get('node_uaid', "default"),
    '#size' =&gt; 50,
    '#maxlength' =&gt; 50,
    '#description' =&gt; t('test UAID.'),
    '#required' =&gt; FALSE,
    '#group' =&gt; 'settingsform'
   );
}


The final objective is a field in the node add/edit vertical form that is directly associated with that node. This field should be accessible in relation to the node.
Unlike building a settings form in Drupal using system_settings_form(), you need to do more than define the form field so that it's processed. You need to define a submit handler so your custom field can be processed. In your hook_form_alter() add a submit handler:

$form['#submit'][] = 'myModule_form_node_form_submit';


Then define your submit handler to process the form value for saving. 

function myModule_form_node_form_submit($form, &amp;$form_state) {
  variable_set('node_uaid', $form_state['values']['node_uaid']);
}