Check Object Jquery

HTML

<div id="res_a"></div>
<div id="res_a1"></div>
<div id="res_a2"></div>
<div id="res_b"></div>
<div id="res_c"></div>
<div id="res_d"></div>

JavaScript

var a = {"provider":"OK!"};
var b = "What is it?";
var c = ["ok","ok1"];
var d = { what: "A regular JS object" };
if($.type(a) == "object"){
  $("#res_a").html($.type(a));
  $("#res_a1").html(a.provider);
}
$("#res_a2").html(a instanceof $?"TRUE":"FALSE");
$("#res_b").html($.type(b));
$("#res_c").html($.type(c));
$("#res_d").html($.type(d));
$("#res_d").append("&nbsp;&nbsp; - "+d.what);