As per the new updated feature ECMAScript 6 (ES6) and ECMAScript 2015, you can use the following options with loops:

for loops

for(var i = 0; i < 5; i++){
  console.log(i);
}

// Output: 0,1,2,3,4

for...in loops

let obj = {"a":1, "b":2}

for(let k in obj){
  console.log(k)
}

// Output: