How to get the id of the element clicked using jQuery

<div class="main_div">
    <div id="inner_div">    
        <span id="d1" class="get_clicked">click to get id</span>
    </div>
</div>

$(document).on('click', 'span', function () {
    alert(this.id);
});

old code

$('span').click(function(){
    alert(this.id);
});

or you can use .on

$('span').on('click', function () {
    alert(this.id);
});

this refers to current span element clicked

this.id will give the id of the current span clicked