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// Global variable
let globalVar = 'Global Variable';

// Local variable declared within the function
function myFunction() {
  let localVar;
  console.log('globalVar:', globalVar); // Global variable
  console.log('localVar:', localVar); // Local variable
}

// Function call
myFunction();

// Output global variable
console.log(globalVar); // Global Variable

// Output local variable // Error! Local variable can only be accessed within the function.
//console.log(localVar); // Error! localVar can only be accessed within myFunction.

# Variable Declaration Keyword - let

`let` is a keyword used in JavaScript to declare variables.

Similar to `var`, it creates variables that store data and can be reassigned. However, variables declared with `let` have `block-level scope`.

> `Block-level scope` means that the variable is accessible only within the block of code enclosed by curly braces.

For instance, if we replace `var` with `let` in the example code from the previous lesson, it would look like this:

```javascript title="let Variable Declaration" 
if (true) {
    let name = "one";
}

console.log(name); // ReferenceError: name is not defined
```

In the code above, the `name` variable declared with `let` is accessible only within the `if` block.

Trying to access the `name` variable outside the conditional statement block composed of `if` will result in a `ReferenceError`.

As such, variables declared with `let` possess block-level scope, meaning they can only be accessed within the block.

<br />

## Reassignable let Variables

A variable declared with `let` can be **reassigned** to a different value after its initial declaration.

```javascript title="Variable Reassignment"
let number = 10;
number = 20; // The value of the variable number is changed to 20

console.log(number); // 20
```

The `let` keyword allows access only inside a specific block of code enclosed by curly braces.

Variable Declaration Keyword - let

Reassignable let Variables

Which of the following correctly describes the characteristics of the let keyword?

Which of the following correctly describes the characteristics of the `let` keyword?