How to listen to when a checkbox is checked in Jquery

Question

I need to know when any checkbox on the page is checked:

e.g.

I tried this in Jquery

Answer 1

$('input:checkbox').live('change', function(){
    if($(this).is(':checked')){
        alert('checked');
    } else {
        alert('un-checked');
    }
});

jsfiddle: http://jsfiddle.net/7Zg3x/1/