What are IIFEs (Immediately Invoked Function Expressions)?

Short answer: Functions that execute immediately after being defined.

Example code

(function() { console.log("Runs instantly!"); })(); Used to create private scopes before let and const.

Real-world example (ShopNest)

ShopNest’s browser cart uses modern JavaScript: fetch APIs with async/await, modules, and clear error handling.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.