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Scope in JavaScript

Explore JavaScript scope concepts including global, local, function, and block scopes. Understand how these scopes restrict variable accessibility, manage resource lifetimes, and enhance code security and debugging for better programming practices.

Scopes restrict access and visibility of variables across a program.

The illustration gives an overview of how the scope can look like in a program. Now, let’s discuss properties.

Scope features

A scope has the following properties:

  • It limits the visibility and accessibility of a variable.
  • It controls the life of the variable and the assigned resources.
  • It helps secure resources and makes debugging easier.

With these features in mind, let’s explore scopes JavaScript.

Scopes in JavaScript

JavaScript has two scopes:

  1. Global scope
  2. Local scope

We will look at them individually.

Global scope

Global scope is the outermost scope in the JavaScript program. In this scope, all variables are accessible by any other scope ...