Loops and Arrays, ES6

const boxes = document.querySelectorAll('.box');

// ES5
//var boxesArr5 = Array.prototype.slice.call(boxes);
//boxesArr5.forEach(function(cur) { cur.style.backgroundColor = 'dodgerblue'});

// ES6

Array.from(boxes).forEach(cur => cur.style.backgroundColor = 'dodgerblue');

// Loops in ES6

for (const cur of boxes) {
    if (cur.className.includes('blue')) {
        continue;
    }
    cur.textContent = 'I changed to blue!';
}

// ES 5

var ages = [12, 17, 8, 21, 14, 11]

 var full = ages.map(function(cur) {
    return cur >= 18;
 });

 console.log(ages);
//A lof of work to get a true or false for ages
console.log(full.indexOf(true));
console.log(ages[full.indexOf(true)]);

// ES 6
// of all the ages, find the index location where cur >= 18
console.log(ages.findIndex(cur => cur >= 18));

console.log(ages.find(cur => cur >= 18));