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JavaScript

JavaScript Scope

JavaScript scope controls where variables can be accessed.

Read Time

5 min read

Difficulty

Beginner

Last Updated

Jun 15, 2026

Version

v1.0.0

Introduction

JavaScript uses scope to secure variables and prevent naming conflicts. If you create a variable inside a function, nothing outside that function can see or use it. This allows developers to use the same variable names in different places safely.

Example

1/* this demonstrates scope */
2function myScope() {
3  let localScore = 50;
4  console.log(localScore); // Works
5}
6// console.log(localScore); // Error!

Key Points

Global scope variables are visible everywhere.
Function scope variables are hidden outside the function.
Block scope (`let` and `const`) hides variables outside curly braces.
Variables declared without keywords become global automatically.

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