CDATA

Can someone kindly explain what this code block is doing?  Inherited code and I am not familiar with CData.

  <script type='text/javascript'>
    //<![CDATA[
      !window.jQuery && document.write(unescape('%3Cscript src="../js/libs/jquery-1.7.1.min.js"%3E%3C/script%3E'));    // scripts concatenated and minified via ant build script
    //]]>
  </script>

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kkbenjAsked:
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StingRaYCommented:
This script includes jQuery framework if it is not included.
CDATA block is a character data block, usually used in XHTML.
If you are writing a plain HTML, you can remove "//<![CDATA[" and "//]]>".
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Robert SchuttSoftware EngineerCommented:
The CDATA part is commented out but could be necessary to maintain valid xml/xsl at some other point.

The javascript code checks if jQuery is available and if not, insert the script tag to include it into the html.
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kkbenjAuthor Commented:
Nothing in XHtml.  Thank you for the information.

One more related question: is that block of code even necessary since:
      <script src='../js/libs/jquery-1.7.1.min.js'></script>
is included in the header?
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StingRaYCommented:
No, it is not necessary anymore.
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kkbenjAuthor Commented:
Thank you both!
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