Javascript - understanding Object.create and Object.call(this)

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I'm trying to fully grasp the MDN documentation on Object.create but I'm left with a few questions that I haven;t able able to crack.

Here is the example code MDN provides.

function Shape() {
  this.x = 0;
  this.y = 0;
}

// superclass method
Shape.prototype.move = function(x, y) {
    this.x += x;
    this.y += y;
    console.info("Shape moved.");
};

// Rectangle - subclass
function Rectangle() {
  Shape.call(this); // call super constructor.
}

// subclass extends superclass
Rectangle.prototype = Object.create(Shape.prototype);
Rectangle.prototype.constructor = Rectangle;

var rect = new Rectangle();

One line I don't understand is Shape.call(this). I've looked up Object.call(this) but I couldn't find any documentation on it. What is this line of code doing?

Also, this line: Rectangle.prototype.constructor = Rectangle; What's the benefit of setting the constructor to Rectangle?

Finally, why would somebody implement use Object.create() over doing something like this:

Rectangle.prototype = new Shape()

Thanks!

asked 1 min ago

user3315416

1