title: how to pass variable from custom module to its tpl
body: <p>I need to know the simplest method to pass variable from custom module to its template<br>
  I have created the custom.module and placed custom.tpl.php in the module folder</p>
  
  <pre><code>function custom_menu(){
    $items = array();
  
    $items['custom'] = array(
      'title' =&gt; t('custom!'),
      'page callback' =&gt; 'custom_page',
      'access arguments' =&gt; array('access content'),
      'type' =&gt; MENU_CALLBACK,
    );
  
    return $items;
  }
  
  function custom_page() {
  
      $setVar = 'this is custom module';
      return theme('custom', $setVar);    
  }
  </code></pre>
  
  <p>i have added theme function but it is not working, can any one suggest me what is wrong with this code</p>
  
  <pre><code>function theme_custom($arg) {
    return $arg['output'];
  }
  
  function custom_theme() {
    return array(
      'Bluemarine' =&gt; array(
          'variables' =&gt; 'output',
          'template' =&gt; 'Bluemarine',
       ),
    );
  }
  </code></pre>