hi to all
i have a strange problem. when i include php file above html tags then its all right
but when i include my header (php file) after html tags then i got this symbol
on browser 
my code when i got this symbol is
<html>
<head>
<title>title</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<link href="css/style.css" rel="stylesheet" type="text/css">
</head>
<body>
<? include("includes/top.php"); ?>
please give me some solution.