How do you handle authentication in a REST API?

Short answer: Typical options include: JWT tokens OAuth API keys Sessions (less common for APIs) 📌 Usually, the client includes a token in the Authorization header: Authorization: Bearer <token> The server verifies the token on every request.

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.