<?php
$app	 = JFactory::getApplication();
$menu = $app->getMenu();
$active = $menu->getActive();
$pageHeading = '';
if ($active) {
  $pageHeading = $active->params->get('page_heading');
}
?>
<h2><?php echo $pageHeading; ?></h2>

$option = JRequest::getCmd('option');
$view 	= JRequest::getCmd('view');
$layout = JRequest::getCmd('layout');
$page 	= JRequest::getCmd('page');
$task 	= JRequest::getCmd('task');
$id 	= JRequest::getInt('id');

$itemid 	= JRequest::getInt('Itemid');

if( $itemid == 123 ) { 
  echo 'this is something';
} else {
  echo 'this is another category';
}