JSFiddle - React, Tailwind, and code Playground

JavaScript

function Person(name, age){
    this.name = name;
    this.age  = age;       
}

Person.foo3 = function() {return 10;};

Person.prototype.foo = function(){
    return Person.foo3();
}

Person.prototype.foo2 = function(){
    return Person.foo3()*2;
}

var wong2 = new Person("wong2", "20");

alert("" + wong2.foo() + ", " + wong2.foo2()); //works

alert("" + Person.foo3()); //works.  this is the distinction between what I'm loosely calling static and private

alert(foo3()); //doesnt work
alert(wong2.foo3()); //doesnt work