Why do we not need to return 'this' from the Media constructor since we are not using the 'new' keyword?

Hey Cale,

Thanks for the input. Here is what I have understood from your comment:

you can use call to make sure values are passed into the relevant parent objects when constructed. For example:

function Person (name, age) {
     this.name = name;
     this.age = age;
}

Person.prototype.add_year = function () {
     this.age = this.age + 1;
};

The call method passes in the values from the Teacher constructor to the Person constructor so that when a new teacher object is instantiated the Person object is pseudo instantiated and it has the values passed in by the call method in the teacher constructor. This is made possible via the prototype chain.

function Teacher (name, age, subject) {
     Person.call(this, name, age);
     this.subject = subject;
}

My assumption: without the prototype chain the values would still be passed to the Person constructor (via call) but the new Teacher object would have no way of accessing them.

Let me know if I'm missing something

your downvotes are because you used to the word "creating". Song.prototype = Object.create(Media.prototype). this line does not create an instance of song, it just runs for all instances of Song. ie, when you do create an instance (or multiple instances) of song, this line will make it so that they have the properties and methods of the Media object.