JavaScript as Prototype-based language

• JavaScript does not contain "classes" that defines a blueprint for the object, such as is found in C++ or Java
• JavaScript uses functions as "classes"
• Everything is an object in JavaScript
• In JavaScript, objects define their own structure
• This structure can be inherited by other objects at runtime

What is a prototype?

• It is a link to another object
• In JavaScript, objects are chained together by prototype chain

Joe -> Person -> Object -> null

• JavaScript objects inherit properties and methods from a prototype

Example of Prototype

• Prototype property allows you to add properties and methods to any object dynamically

function Animal(name) {
  this.name = name
}

Animal.prototype.age = 10

• When object Cat is inherited from object Animal
  • Then Animal is the prototype object or the constructor of the Cat

var cat = new Animal('cat')
console.log(cat) // constructor: "Animal"
console.log(cat.name) // cat
console.log(cat.age) // 10

I love jotting down my thoughts on my blog Ninja Academy. And, if you are looking to level up your Web Development chops, do check out my Ultimate Web Development Bootcamp.