Javascript Map, Filter, Reduce Usage

mapFilterReduce.js

var a = [1,2,3,4,5];

//MAP
var mapped = a.map(function(number) {
    return number * 2;
});

console.log(mapped);

//FILTER
var filtered = a.filter(function(number) {
    return number % 2;
});

console.log(filtered);

//REDUCE
var reduced = a.reduce(function(prevNumber, currentNumber) {
   return  prevNumber + currentNumber;
});

console.log(reduced);