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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();

// Print global variable
console.log(globalVar); // Global variable

// Print local variable // Error! Local variables are accessible only within the function.
//console.log(localVar); // Error! localVar is only accessible within myFunction.

# Variable Declaration Keyword - let

`let` is one of the keywords used to declare variables in JavaScript.

Like `var`, it serves to store data but with some important differences.

Variables declared using `let` have `block-level scope`.

Similar to paragraphs or passages in a book, code also has sections enclosed by curly braces `{ }`, known as 'blocks'.

`let` creates variables that are only accessible within this block.

<br />

## Basic Usage

You can declare a variable and assign a value using the `let` keyword.

Example:

```javascript title="let Variable Declaration"
let schoolName = 'Lincoln High School';
```

In this example, the variable named `schoolName` holds the string value 'Lincoln High School'.

<br />

## Characteristics of let Variables

1. **Reassignable**: Variables declared with `let` can be reassigned to different values.

```javascript title="Reassigning let Variable"
let age = 15;
age = 16; // The value of the variable age is changed to 16.
```

<br />

2. **Block-Level Scope**: Variables declared with `let` can only be accessed within the block, and its inner blocks, where it was declared.

Example:

```javascript title="let Variable Block-Level Scope"
if (true) {
  let message = 'Hello!';
  console.log(message); // Outputs 'Hello!'
}

// The message variable cannot be used here.
```

The `let` keyword provides block-level scope when declaring a variable. This means the variable is only accessible within the curly braces that enclose the block.

Variable Declaration Keyword - let

Basic Usage

Characteristics of let Variables

What is one of the characteristics of the let keyword?

What is one of the characteristics of the `let` keyword?