javascript classes

they are prototypes.

A class is a blueprint for create object instances, a prototype IS an instance that other object instances delegate work to, a prototype is not a blueprint, it actually exists, it is there.

This is why you can actually add a new method to Array and suddenly all arrays can use it. This can be done in runtime, affecting an already instanced object.

var someArray = [1, 2, 3];

Array.prototype.newMethod = function() {  
  console.log('I am a new method!');  
};
someArray.newMethod(); // I am a new method!

// The above code would not be possible with real classes, because 
// modifying a blueprint does not modify whatever was built with it.

In short, classes in Javascript are syntactic sugar for Prototype Inheritance.