Map operator js

let cars = ['Mersedes', 'Reno', 'BMW', 'Porsche']
let up = =>{
      return car.toUpperCase()

can someone explain, how is parametr ‘car’ is connected to array ‘cars’? how this return can effect the array?

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Hey @alastrenok ,

The .map takes your callback and passes in the values inside the cars. This is what a .map function would look like: = function(callback) {
  for (let i = 0; i < this.length; i++) {
    callback(this[i])// 'this' is the array.

So essentially, the map function takes your function and run it by giving it the variable.

Here’s a more detailed and easier to understand explanation from an MDN article: