What is load balancing and how does it apply to Node.js?

Short answer: Load balancing distributes incoming requests across multiple server instances to: Improve performance Increase availability and fault tolerance In Node.js, you can: Use the cluster module to spawn workers on multiple CPU cores. Use external load balancers like Nginx, HAProxy, or cloud load balancers. PM2 also supports clustering with: pm2 start app.js -i max

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.