What is the difference between browser global scope and Node.js global scope?

The difference between browser global scope and Node.js global scope primarily revolves around how global variables are treated and accessed in each environment.

Browser Global Scope

In a web browser, the global scope is represented by the window object. Any variable declared with the var keyword in the global scope becomes a property of the window object. This means that if you declare a variable like var x = 5; in the global scope of a browser, you can access it as window.x. The window object serves as the top-level scope, and all global variables and functions declared with var and function keywords are attached to this object. This makes them accessible from anywhere in the browser's JavaScript environment[3][4].

Node.js Global Scope

In contrast, Node.js handles global scope differently. The top-level scope in a Node.js module is not the global scope but the module scope itself. This means that variables declared with var, let, or const within a module are local to that module and are not added to the global object, known as global in Node.js. If you want a variable to be global across modules in Node.js, you must explicitly attach it to the global object, like global.x = 5;. This design prevents variables from different modules from colliding with each other and enhances modularity and encapsulation[1][2][3].

Key Differences

1. Scope Attachment: In browsers, variables declared in the global scope ...