can any one tell me what does these codes signify in html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>EMCO</title>
<link href="site.css" type="text/css" rel="stylesheet" />
<script type="text/javascript" language="JavaScript1.2" src="menu/stmenu.js"></script>
<script type="text/javascript" language="JavaScript1.2" src="AC_RunActiveContent.js"></script>
<script type="text/javascript" language="javascript">
function SearchSite()
{
document.location.href='http://www.emcoindia.com/search.html?cx=002343543654529033385:qxdcrdw2omi&cof=FORID%3A11&ie=UTF-8&q=' + document.getElementById('txtSearch').value + '&sa=Search';
}
</script>
<script type="text/javascript" language="javascript" src="AC_OETags.js"></script>
<script language="JavaScript" type="text/javascript">
<!--
// -----------------------------------------------------------------------------
// Globals
// Major version of Flash required
var requiredMajorVersion = 8;
// Minor version of Flash required
var requiredMinorVersion = 0;
// Minor version of Flash required
var requiredRevision = 0;
// -----------------------------------------------------------------------------
// -->
can any one tell me what does these codes signify in html