Understand filter(), map(), reduce() in 10 seconds

filter-map-reduce.js

// FILTER(), MAP(), REDUCE()
const boxs = [1, 3, 5, 8, 6, 7, 9];

// FITER()
// This method creates a new array if the items of an array pass a certain condition.

const boxFilter = boxs.filter(box => {
  if (box > 3) {
    return box;
  }
})
console.log(boxFilter)

// MAP()
// This method creates a new array by manipulating the values in an array.

const boxMap = boxs.map(box => {
  return '$' + box;
})
console.log(boxMap)

// REDUCE()
// This method is good for calculating totals, it converts an array into a single value.

const boxReduce = boxs.reduce((accumulator, value) => {
  return accumulator + value;
}, 0)
console.log(boxReduce)

Copy the above code into your console and run to see the results.
If you have further questions, feel free to ask! 👍