jQuery 1.11.0 and jQuery 2.0.1 has officially been released simultaneously. jQuery is a  JavaScript library which simplifies client-side scripting of HTML5. If you’ve already upgraded to 1.9/2.0 then this won’t cause you any problems but if your trying to update older code use the jQuery 1.9 upgrade guide. If you want to know more about jQuery or the changes implemented head over to the jQuery site.
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