I'm having difficulties understanding this code. Help plss

Question

var s = [23, 65, 98, 5];
Array.prototype.myMap = function(callback) {
var newArray = [];
this.forEach(a => newArray.push(callback(a)));
return newArray;
};
var new_s = s.myMap(function(item) { return item * 2; });

Answer 1

https://code.sololearn.com/WS2QJ8nUp6wQ/?ref=app