It doesn't have classes or inheritance.

You don't count this as inheritance? Also, classes aren't required for OOP.

    function Parent() {
        // somestuff
    }
    function Child() {
        Parent.call(this);
    }
    Child.prototype = new Parent();
    Child.prototype.constructor = Child

I call that prototypical construction. The point is, it's hardly java.

Neither classes nor inheritance are necessary for OOP. A good read on this topic: http://wcook.blogspot.de/2012/07/proposal-for-simplified-mod...

Btw, you can also do classes with JavaScript: http://mootools.net/docs/core/Class/Class

JavaScript's prototype-based OOP is a superset of class-based OOP.