Run this function to give control of the $ variable back to whichever library first implemented it. This helps to make sure that jQuery doesn't conflict with the $ object of other libraries. By using this function, you will only be able to access jQuery using the 'jQuery' variable. For example, where you used to do $("div p"), you now must do jQuery("div p"). Maps the original object that was referenced by $ back to $ jQuery.noConflict(); // Do something with jQuery jQuery("div p").hide(); // Do something with another library's $() $("content").style.display = 'none'; Reverts the $ alias and then creates and executes a function to provide the $ as a jQuery alias inside the functions scope. Inside the function the original $ object is not available. This works well for most plugins that don't rely on any other library. jQuery.noConflict(); (function($) { $(function() { // more code using $ as alias to jQuery }); })(jQuery); // other code using $ as an alias to the other library