What are worker threads in Node.js?

Short answer: Worker threads allow you to run JavaScript code in parallel on multiple threads within the same process — useful for CPU-intensive tasks like image processing or complex calculations without blocking the main event loop. const { Worker } = require('worker_threads');

Example code

const worker = new Worker('./worker.js');
worker.on('message', (msg) => console.log('From worker:', msg)); worker.postMessage('start');

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.