Just a quick example

prototypal-inheritance.js

const Dog = {
  woof () { return `Woof! I am ${this.name}!` }
}

const Yoko  = Object.assign(Object.create(Dog), { name: 'Yoko' })
const Yoshi = Object.assign(Object.create(Dog), { name: 'Yoshi' })

Yoko.woof()  // Returns 'Woof! I am Yoko!'
Yoshi.woof() // Returns 'Woof! I am Yoshi!'

Dog.woof = function () { return `W000f! I am still ${this.name}, but much cooler!` }

Yoko.woof()  // Returns 'W000f! I am still Yoko, but much cooler!'
Yoshi.woof() // Returns 'W000f! I am still Yoshi, but much cooler!'