JS Data Structures: Arrays, see more at: https://medium.com/p/e1bc57bda950

DATA_STRUCTURES_reverseArray.js

const animals = ['elephant', 'monkey', 'snake', 'lion', 'zebra']

const reverseArray = currentArray => {
  for (let index = 0; index < currentArray.length / 2; index++) {
    const currentItem = currentArray[index]
    const otherItem = currentArray[currentArray.length - 1 - index]

    currentArray[index] = otherItem
    currentArray[currentArray.length - 1 - index] = currentItem
  }

  return currentArray
}

const animalsReversed = reverseArray(animals)

console.log(animalsReversed) // will return [ 'zebra', 'lion', 'snake', 'monkey', 'elephant' ]