how get checkbox if checked in jquery

//using plane javascript 
if(document.getElementById('on_or_off_checkbox').checked) {
    //I am checked
} 

//using jQuery
if($('#on_or_off_checkbox').is(':checked')){
    //I am checked
}$("checkbox").is(":checked")if($("#rule").is(":checked")){
    $("#form").submit();
 }$('#' + id).is(":checked")