JAVASCRIPT

multiselect_1

<script src="//ajax.googleapis.com/ajax/libs/jquery/2.0.3/jquery.min.js"></script>

multiselect_2

<!-- Build your select: -->
<select id="example-getting-started" multiple="multiple">
    <option value="cheese">Cheese</option>
    <option value="tomatoes">Tomatoes</option>
    <option value="mozarella">Mozzarella</option>
    <option value="mushrooms">Mushrooms</option>
    <option value="pepperoni">Pepperoni</option>
    <option value="onions">Onions</option>
</select>

multiselect_3

<!-- Initialize the plugin: -->
<script type="text/javascript">
    $(document).ready(function() {
        $('#example-getting-started').multiselect();
    });
</script>