$(...).DataTable is not a function
<p>I use datatables in jquery but not working. I can help. This is the script. Thanks! The #userList is a div thtat contain a table-striped table-condensed order-columns table-bordered. Thanks!</p>

<pre><code> $('#userList').DataTable({
    sortable: true,
    processing: true,
    serverSide: true,
    ajax: {
        url: 'include/dades_customers.php',
        type: 'POST'
    },
    columns: [
        {"data": "CustName"},
        {"data": "Address1"},
        {"data": "Address2"},
        {"data": "City"},
        {"data": "PostCode"},
        {"data": "State"},
        {"data": "Country"},
        {"data": "Phone"},
        {"data": "Fax"},
        {"data": "Web"}
    ],
    lengthMenu: [ 2, 5, 10, 25, 50, 75, 100 ],
    //dom: '&lt;"H"fi&gt;rt&lt;"F"lp&gt;&lt;"clear"&gt;'

    dom: '&lt;"top"fiB&gt;&lt;"content"rt&gt;&lt;"footer"lp&gt;&lt;"clear"&gt;',
    buttons: [ 'colvis' ]

    /*footerCallback: function( tfoot, data, start, end, display ) {
        var api = this.api();
        $( api.column( 5 ).footer() ).html(
            api.column( 5 ).data().reduce( function ( a, b ) {
                return a + b;
            }, 0 )
        );
    }
    */  
});
</code></pre>