what does static do in javascript code example

Example 1: static js

// the static method is a method which cannot be called through a class instance.
class Point {
  constructor(x, y) {
    this.x = x;
    this.y = y;
  }

  static distance(a, b) {
    const dx = a.x - b.x;
    const dy = a.y - b.y;

    return Math.hypot(dx, dy);
  }
}

const p1 = new Point(7, 2);
const p2 = new Point(3, 8);

console.log(Point.distance(p1, p2));

Example 2: js static methods

class Foo(){   static methodName(){      console.log("bar")   }}

Example 3: javascript class static method

// *** JS Class STATIC method ***   

class Animal {
        sayHello() {
            return `${this.constructor.greeting}! I'm ${this.name}!`;
        }
    }

    class Cat extends Animal {
        constructor(name) {
            super(); // connects parent to child/constructor
            this.name = name; //=> need this line otherwise name undefined
        }
        static greeting = 'Feed me';
    }

    class Dog extends Animal {
        constructor(name) {
            super();
            this.name = name; // same output type as above
        }
        static greeting = 'Sigh';
    }

    const run = document.getElementById("run");
    run.addEventListener('click', () => {
        let Garfield = new Cat('Garfield');
        let Snoopy = new Dog('Snoopy');
        console.log(Garfield.sayHello());
        console.log(Snoopy.sayHello());
    })
// output = Feed me! I'm Garfield! Sigh! I'm Snoopy!

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