when to use OOP in javascript code example

Example 1: js oop

function Person(name) {
  this.name = name;
  this.greeting = function() {
    alert('Hi! I\'m ' + this.name + '.');
  };
}

Example 2: js oop

function createNewPerson(name) {
  var obj = {};
  obj.name = name;
  obj.greeting = function() {
    alert('Hi! I\'m ' + this.name + '.');
  };
  return obj;
}