In what scenario would you use an IIFE in JavaScript?

Using an Immediately Invoked Function Expression (IIFE) creates a local scope that encapsulates variables and functions within it. This is particularly useful for avoiding pollution of the global namespace, which can lead to variable collisions and unexpected behaviors when multiple scripts interact with the same global variables.

When an IIFE is executed, it defines its own scope that prevents any declarations inside it from being accessible or modifying the global variables. For instance, if there are variables defined inside the IIFE, they will not interfere with other variables outside of that function. This helps developers maintain clean code organization and avoid unintended side effects, especially in larger applications where many different scripts may be executing.

In contrast, while an IIFE is a function that executes immediately, it is not particularly designed to create reusable functions, handle errors in asynchronous code, or define new variable types. Instead, its primary purpose is to encapsulate code within its own scope, thereby keeping global variables safe from inadvertent modifications.