.addBack()
Add the previous set of elements on the stack to the current set, optionally filtered by a selector.
Category: Version 1.8
Aspects of the API that were changed in the corresponding version of jQuery. API changes in jQuery 1.8.0 dealt primarily with animations and the removal of some methods such as deferred.isResolved(), deferred.isRejected(), $.curCSS(), $.attrFn(), and $(element).closest(Array) returning Array.
For more information, see the Release Notes/Changelog at http://blog.jquery.com/2012/08/09/jquery-1-8-released/
deferred.pipe()
Utility method to filter and/or chain Deferreds.
:eq() Selector
Select the element at index n within the matched set.
jQuery.parseHTML()
Parses a string into an array of DOM nodes.