Does not support Hoisting
The behavior of moving the declarations on top of the script is known as hoisting.
Example: Let do not support hoisting.
x = 12;
console.log(x);
let x;
Output:
Uncaught ReferenceError: Cannot access 'x' before initialization
Supported Browser:
- Chrome 49 and above
- Edge 14 and above
- Firefox 44 and above
- Opera 17 and above
- Safari 10 and above
P.S: To clear your concept of var, and const, and let please go through How to declare variables in different ways in JavaScript?
JavaScript Let
The let keyword in JavaScript is used to make variables that are scoped to the block they’re declared in. Once you’ve used let to define a variable, you cannot declare it again within the same block. It’s important to declare let variables before using them.
The let keyword was introduced in the ES6 or ES2015 version of JavaScript. It’s usually recommended to use let when you’re working with JavaScript.
Syntax:
let variable_name = value;