Swap numbers [a, b] = [b, a]; Unique array values let unique = [...new Set(array)]; Sum array.reduce((accumulator, item) => accumulator + item.value, 0); Max value of object property in array Math.max(...array.map((object) => object[property])); Longest string in an array array.reduce((a, b) => (a.length > b.length ? a : b), "");