function Shape(){
this.x = 0;
this.y = 0;
}
Shape.prototype.move = function (x, y){
this.x += x;
this.y += y;
console.info('Shape moved.');
}
function Rectangle(){
Shape.call(this);
}
Rectangle.prototype = Object.create(Shape.prototype);
Rectangle.prototype.contructor = Rectangle;
var rect = new Rectangle();
rect.move(1, 1);