Global object in JS

About

Every JavaScript environment has one special object called the global object. It has features like: -

• setTimeout
• console
• Math
• Date
• Array
• JSON
• parseInt

Conceptually, both the below code blocks are same.

// For Example:
console.log(Math.PI);
console.log(setTimeout);
console.log(Date);

&&

globalObject.Math
globalObject.Date
globalObject.console

History

In the browser, it is called window.

window.Math === Math
// true

window.Date === Date
// true

window.console === console
// true

In a run time environment like Node, it is called global.

global.setTimeout
global.console
global.Buffer

However, in workers, it was called self.
So to make it less annoying,
ES20, introduced globalThis.

1. For Browsers, javascript globalThis === window // true javascript

2. For run time environments
   

   globalThis === global
   // true
   

3. For web workers
   

   globalThis === self
   // true