This figure again shows that every object has a prototype. Constructor function Foo also has its own
__proto__
which is Function.prototype, and which in turn also references via its__proto__
property again to the Object.prototype. Thus, repeat, Foo.prototype is just an explicit property of Foo which refers to the prototype of b and c objects.
var b = new Foo(20);
var c = new Foo(30);````
What are the differences between __proto__ and prototype properties?
![Paste_Image.png](http://upload-images.jianshu.io/upload_images/4766759-2dd51925ea01d038.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
来源:http://stackoverflow.com/questions/9959727/proto-vs-prototype-in-javascript