Classical Vs Prototypal Inheritence 

Classical Inheritence:
    - Ways of sharing variable and methods...etc 
    - Very verbose 

Prototypal Inheritence:
    - Simpler than Classical

Example:

obj: have property prop1 so we can do obj.prop1

--Javascript Engine adds hidden properties or method to things:

All object in Javascript have a prototype property:

The property is simply a reference to another object (eg: __proto__). 

It is an object that stands on its own, could use it by itself if we wanted to. 
But the object property that we called __proto__ thats its prototype, 
Thats the object that is going to grab and get its properties and methods
Object proto in objb has property: prop2 , so we can do obj.prop1
This is called the prototype chain. 

Eg:
var person = {
    firstname = 'Default', 
    lastname = 'Default',
    getFullName: function(){
        return this.firstname + this.lastname;
    }
}

var john = {
    firstname: 'John',
    lastname: 'Doe'
}

--Alert not used this way to declare prototype as its a performance problem - DEMO PURPOSE ONLY:
john._proto_ = person; 
console.log(john.getFullName()); // John Doe
console.log(john.firstname); //John - Because of Prototype Chain as it stops the first time if finds what is is looking for 

var jane = {
    firstname = 'Jane'
}

jane._proto_ = person;
console.log(jane.getFullName()); //Jane Default