What are worker threads in Node.js and when should you use them?

Short answer: Worker threads run JavaScript code in parallel threads — useful for CPU-intensive tasks that block the event loop. Use them when your app needs heavy computation without blocking other requests.

Real-world example (ShopNest)

A ShopNest BFF in Node.js aggregates catalog and price APIs for the React storefront.

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.