4. this in the class constructor function Person

01

Using the this keyword in the constructor function or class, Person, will allow us to add the method as a properties/attributes to the 'instance' of Person me 

function Person(){
    this.talk = function(){
        return 'Talking'
    }
}
const me = new Person()
me

The this keeps the talk method in the instance and not in it's Person prototype

02

The talk() method is now stored as an attribute to the instance me of parent class/funciton Person. 

me.__proto__
Person.prototype
Person

The method is not longer stored in prototype or __proto

03

We don't use this frequently b/c it will copy the function into each instance of the class, is not needed

Here, we see that when using this in the 'Prototype' class Person if will appear as undefined when logged, that is b/c as we have said this whole page... 

function Person(){
    this.age = 12
}
const me = new Person()
me.age
Person.age

The this atrribute, age and its value get applied to the 'instance' of the class and not to the class itself