Like every framework, Ember.js has predefined objects and classes, which are at our disposal. In most cases, we will extend them and write only the custom logic, which is a part of your application. All the ready-to-use classes are under the Ember namespace. This means that whenever we want to use some part of the framework, we need to go through the Ember. notation. For example, in the class extending shown in the following code:

App.Person = Ember.Object.extend({
  firstname: '',
  lastname: '',
  hi: function() {
    var name = this.get("firstname") + " " + this.get("lastname");
    alert("Hello, my name is " + name);
  }
});
var person = App.Person.create();
person.set("firstname", "John");
person.set("lastname", "Black");
person.hi();

We defined a class called Person. It has two properties and only...