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What is the meaning of symbol $ in jQuery?

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By User


What does '$' - sign in JQuery stand for?



Source: Tips4all, CCNA FINAL EXAM
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  1. UserMay 19, 2012 at 2:35 AM

    It is syntactic sugar. It is not specific only to jQuery, other libraries use it as well.
    You can look for a full details article about the use of dollar sign in Javascript here.

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  2. UserMay 19, 2012 at 2:35 AM

    The JQuery object :)

    From the JQuery doc:


    By default, jQuery uses "$" as a shortcut for "jQuery"


    So, using $("#id") or jQuery("#id") is the same

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  3. UserMay 19, 2012 at 2:35 AM

    As said in other answers $ is a shortcut to the jQuery function.

    Some JavaScript libraries uses $ too (example: prototype). To avoid conflict with those other libraries jQuery provides jQuery.noConflict() function. Calling this function the control of the $ variable goes back to the other library that first implemented it. Doing this to use jQuery you can't do this $('div.someClass') anymore, instead jQuery('div.someClass').

    Alternatively can do this:

    jQuery.noConflict();

    jQuery.ready(function($) {
    // use $ for jQuery
    }

    //use $ for the other library


    When writing plugins to avoid problems with the usage of noConflict you can pass 'jQuery' to a function:

    function($) {

    //use $ writing your plugin

    }(jQuery)

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