For for (let i=0; i < 10; i++) { console.log('Loop ' + i); } // or in one line for (let i=0; i < 10; i++) console.log('Loop ' + i); For without arguments let i = 0; // we have i already declared and assigned for (; i < 3; i++) { // no need for "begin" alert( i ); // 0, 1, 2 } // same as while (i < 3) let i = 0; for (; i < 3;) { alert( i++ ); } Continue & break for (let i=0; i < 10; i++) { if (i == 3) continue; // skip if (i == 9) break; // end loop console.log('Loop ' + i); } While let i = 0; while (i < 3) { i++; // 0, 1, 2 console.log(i); } Do let i = 0; do { i++; console.log(i); } while (i < 10) Labels for break/continue // break out from nested loops outer: for (let i = 0; i < 10; i++) { for (let j = 0; j < 10; j++) { if (j == 5) break outer; console.log(i, j); } } console.log('done'); for...in Iterates over all enumerable properties of an object that are keyed by strings (ignoring ones keyed by Symbols) let obj = { name: "John", age: 30, isAdmin: true }; // iterates over properties of an object for (let key in obj) { console.log( key, obj[key] ); // name John, age 30, isAdmin true } for...of Iterates over iterable objects const arr = ['a', 'b', 'c']; for (const element of arr) { console.log(element); // a b c } forEach Executes a provided function once for each array element const arr = ['a', 'b', 'c']; arr.forEach(element => console.log(element)); // a b c