// Using let (can be changed) let score = 10; score = 20; // This works console.log(score); // 20 // Using const (cannot be reassigned) const MAX_USERS = 100; // MAX_USERS = 200; // Error! Can't change a constant // Block scope with let if (true) { let message = 'Hello'; console.log(message); // Works here } // console.log(message); // Error! message is not defined here