Originally from this tweet
[1, 2, 3, 4].at(1) // 2
[1, 2, 3, 4].pop() // [1, 2, 3]
[1, 2, 3, 4].push(5) // [1, 2, 3, 4, 5]
[1, 2, 3, 4].fill(1) // [1, 1, 1, 1]
[1, 2, 3, 4].join('-') // '1-2-3-4'
[1, 2, 3, 4].shift() // [2, 3, 4]
[1, 2, 3, 4].reverse() // [4, 3, 2, 1]
[1, 2, 3, 4].unshift(1) // [1, 1, 2, 3, 4]
[1, 2, 3, 4].includes(2) // true
[1, 2, 3, 4].map(num => num * 2) // [2, 4, 6, 8]
[l, 2, 3, 4].some(num => num > 3) // true
[l, 2, 3, 4].find(num => num > 2) // 3
[l, 2, 3, 4].every(num => num > 3) // false
[1, 2, 3, 4].filter (num => num > 2) // [3, 4]
[1, 2, 3, 4].findIndex(num => num > 2) // 2
[1, 2, 3, 4].reduce( (acc, num) => acc + num) // 10
// JavaScript Array methods (by @denicmarko)
More can be found on Markos blog