Пример файла header.php

<!DOCTYPE html PUBLIC '-//W3C//DTD XHTML 1.0 Strict//EN'; 'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd'>
<html xmlns='http://www.w3.org/1999/xhtml' xml:lang='ru' lang='ru'>
<head>
<title><?$APPLICATION->ShowTitle();?></title>
<?$APPLICATION->ShowHead();?>
</head>
<body>
<?$APPLICATION->ShowPanel();?>