what is object oriented programming principles javascript code example

Example: How to use Object Oriented Programming Principles in Javascript

class Shape {  get area() {    return 0;  }}class Rectangle extends Shape {  constructor(length, width) {    super();    this.length = length;    this.width = width;  }  get area() {    return this.length * this.width;  }}class Square extends Shape {  constructor(length) {    super();    this.length = length;  }  get area() {    return this.length ** 2;  }}class Circle extends Shape {  constructor(radius) {    super();    this.radius = radius;  }  get area() {    return Math.PI * (this.radius ** 2);  }}const shapes = [  new Rectangle(1, 2),  new Square(1, 2),  new Circle(2),]for (let s of shapes) {  console.log(s.area);}