What are JWTs and how do you use them?

Short answer: JWT (JSON Web Token) is a compact, URL-safe token used for securely transmitting information. Consists of Header, Payload, and Signature Used to verify user identity and permissions 📌 Generate: const jwt = require('jsonwebtoken'); const token = jwt.sign({ id: user.id }, 'secret', { expiresIn: '1h' }); 📌 Verify: jwt.verify(token, 'secret');

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.