javascript objects / methods

simple object is created as below
var myFriend = new Object();
        myFriend.firstname = "rythm";
        myFriend.lastname = "algo";
other way to instantiate is
  var myFriend = {
            firstname: " rythm ",
            lastname: " algo "
        };
Also to add a method
var myFriend = {
            firstname: " rythm ",
            lastname: " algo ",
            printdetails: function() {
                alert("Hi " + this. firstname);
                alert ("Hi " + this lastname );
            }
        };
We can use the method as below
myFriend. printdetails ();

update:
myFriend. firstname = "ram";
myFriend ["firstname "] = "patrick";
delete:
delete myFriend. firstname;
delete myFriend["firstname "];

for (var prop in myFriend) {
console.log("Name: " + prop + " Value: " + myFriend [prop]);
}
delete myData.printdetails;

The Equality Operator vs. the Identity Operator
var firstVal = 5;
var secondVal = "5";
if (firstVal == secondVal) { This compares only values
if (firstVal === secondVal) {  this checks type also