how to open a window in javascript code example

Example 1: javascript open new window

<a onclick="window.open(document.URL, '_blank', 'location=yes,height=570,width=520,scrollbars=yes,status=yes');">
Open New Window
</a>

Example 2: open new window in java script

<script type="text/javascript">
var windowObjectReference = null; // global variable

function openFFPromotionPopup() {
  if(windowObjectReference == null || windowObjectReference.closed)
  /* if the pointer to the window object in memory does not exist
     or if such pointer exists but the window was closed */

  {
    windowObjectReference = window.open("http://www.spreadfirefox.com/",
   "PromoteFirefoxWindowName", "resizable,scrollbars,status");
    /* then create it. The new window will be created and
       will be brought on top of any other window. */
  }
  else
  {
    windowObjectReference.focus();
    /* else the window reference must exist and the window
       is not closed; therefore, we can bring it back on top of any other
       window with the focus() method. There would be no need to re-create
       the window or to reload the referenced resource. */
  };
}
</script>

(...)

<p><a
 href="http://www.spreadfirefox.com/"
 target="PromoteFirefoxWindowName"
 onclick="openFFPromotionPopup(); return false;"
 title="This link will create a new window or will re-use an already opened one"
>Promote Firefox adoption</a></p>