Jquery not working.. Uncaught TypeError: Object # has no method 'ready'

I am trying to add this script in my application.

<script src="mootools-1.2-core-yc.js" type="text/javascript"></script>

    <script src="mootools-1.2-more-drag.js" type="text/javascript"></script>

But get this error message.

"Jquery not working.. Uncaught TypeError: Object # has no method 'ready'"

Reason is my application already has this line of code.

$(document).ready(function () {

    $(".FreeTextBoxDescription_DesignBox").css({ 'background-color': 'White' });

    $('#closeBtnLike').click(function () {

        $('#smallPopupBoxLikeOnComment').hide();

        $('#overlay').hide();

    });

});

Solution.

This is happening because of Jquery and mootools conflict

$(document).ready(function(){

Replace with

jQuery(document).ready(function($) {

It is because of, both Jquery and mootools use $(document).