JavaScript Expand Window

<script language="JavaScript">
window.onload = maxWindow;

function maxWindow() {
window.moveTo(0,0);

 if (document.all) {
   top.window.resizeTo(screen.availWidth,screen.availHeight);
 } else if (document.layers || document.getElementById) {
   if (top.window.outerHeight<screen.availHeight || top.window.outerWidth<screen.availWidth) {
     top.window.outerHeight = screen.availHeight;
     top.window.outerWidth = screen.availWidth;
   }
 }
}
</script>