Prototype Property

__proto__ Property

In JavaScript, objects contain a property [[Prototype]] that is hidden. This property either points to another object or is null.

The [[Prototype]] property of objects, i.e., anObject.[[Prototype]] defines the prototype of anObject. It is defined through the __proto__ property which is used as a setter/getter for the [[Prototype]] property; i.e., __proto__ is used in order to access/set the [[Prototype]] property of an object.

Syntax

Let’s take a look at the syntax for accessing and setting the [[Prototype]] property of an object.