JavaScript_Succinctly

In this example, the foo property is found within the prototype object. You need to
realize this is only possible because of the association between the instance of Array()
and the Array() constructor prototype object (i.e. Array.prototype). Simply put,
myArray.__proto__ (or myArray.constructor.prototype) references
Array.prototype.
Last stop in the prototype chain is Object.prototype
Since the prototype property is an object, the last stop in the prototype chain or lookup
is at Object.prototype. In the code that follows, I create myArray, which is an empty
array. I then attempt to access a property of myArray that has not yet been defined,
engaging the prototype lookup chain. The myArray object is examined for the foo
property. Being absent, the property is looked for at Array.prototype, but it is not
there either. So the final place JavaScript looks is Object.prototype. Because it is not
defined in any of those three objects, the property is undefined.
Sample: sample123.html
var myArray = [];
console.log(myArray.foo) // Logs undefined.
/* foo was not found at myArray.foo or Array.prototype.foo or
Object.prototype.foo, so it is undefined. */
Take note that the chain stopped with Object.prototype. The last place we looked for
foo was Object.prototype.
Notes
Careful! Anything added to Object.prototype will show up in a for in loop.
The prototype chain returns the first property match it finds in the
chain
Like the scope chain, the prototype chain will use the first value it finds during the
chain lookup.
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