new创建对象的过程发生了什么

var Person = function() {
    this.aaa = "aaa";
    this.bbb = "bbb";
    this.ccc = function() {
        alert(this.aaa);
    };
}
var person1 = new Person();
person1.ccc();

var person2 = new Object();
Person.call(person2);  // call : fun.call(thisArg, arg1, arg2, ...)
person2.__proto__ = Person.prototype;