What is the role of a CDN (Content Delivery Network) in improving API performance?

Short answer: A CDN caches and delivers static or semi-static content from edge servers close to users. Reduces latency and improves response times. Helps with traffic offloading, reducing load on origin servers. Supports DDoS protection and scaling under heavy loads. 👉 Example: Cloudflare, Akamai, AWS CloudFront.

Real-world example (ShopNest)

ShopNest exposes REST APIs for cart and checkout. Controllers stay thin; business rules live in application services.

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.