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// Check block-level scope
if (true) {
  let message = 'Hello!';

  console.log(message); // Outputs 'Hello!'
}

// The message variable below is declared outside the scope, resulting in an error.
console.log(message); // ReferenceError: message is not defined

# Scope

In JavaScript, `scope` refers to the `range` within which variables can be accessed.

<br />

The scope of `var` ignores the code block enclosed by curly braces `{ }`.

```javascript title="var scope"
if (true) {
    var name = "one";
}

console.log(name); // "one"
```

In the code above, the `name` variable declared with `var` is defined within the `if` block, but it can also be accessed outside the `if` block.

> *Note*: The `if` keyword is used to create conditional statements. The condition is placed inside the parentheses, and the code to be executed is placed within the curly braces `{ }`. In the conditional statement above, since `true` is always true, the code inside the `if` block is executed.

<br />

Types of scopes include `global scope`, `local scope`, `block scope`, and `function scope`.

We will explore the characteristics of each type of scope with practical examples later on.