function lumen_regions() {
  
  $regions = array(
    'site_header'     => t('site header'),    // page.tpl.php -> $site_header
    'content'         => t('main content'),   // page.tpl.php -> $content
    'left'            => t('sidebar left'),   // page.tpl.php -> $sidebar_left
    'right'           => t('sidebar right'),  // page.tpl.php -> $sidebar_right
    'site_footer'     => t('site footer'),    // page.tpl.php -> $site_footer
  );
  
  // Passed to lumen_node() for node specific regions.
  $regions['node_block'] = t('node -all types');  // node.tpl.php -> $node_region
  // Each node type region shares the same variable and template.
  foreach (node_get_types('names') as $type => $name) {
    $regions['node_block_'. $type] = t('node !type', array('!type' => $name));
  }
  
  // Passed through phptemplate_comment_wrapper() -in this file. It is *not* added to each comment.
  // If comments are disabled or the viewer does not have permmission to view, then the region will not show.
  $regions['comment_block'] = t('comment -all types'); // templates_overrides/comment_wrapper.tpl.php -> $comment_region
  // Each node type region shares the same variable and template.
  foreach (node_get_types('names') as $type => $name) {
    $regions['comment_block_'. $type] = t('comment !type', array('!type' => $name));
  }
    
  return $regions;
}