Node.js là gì? Tại sao dùng cho backend?

Node.js là runtime JavaScript trên server, dùng V8 engine.

• Ưu điểm: non-blocking I/O xử lý nhiều requests đồng thời, cùng ngôn ngữ với frontend (JS) nên team dùng chung tooling và type definitions, npm ecosystem khổng lồ với hàng triệu packages, fit cho real-time apps (chat, notifications) nhờ event-driven model.
• Thường dùng cho API servers, microservices, BFF (Backend for Frontend) — không phù hợp CPU-intensive workloads (video encoding, ML inference) vì single-threaded event loop bị block.

Node.js is a server-side JavaScript runtime powered by the V8 engine.

• Advantages: non-blocking I/O handles many concurrent requests, same language as the frontend (JS) lets the team share tooling and type definitions, a massive npm ecosystem with millions of packages, and excellent fit for real-time apps (chat, notifications) thanks to its event-driven model.
• Commonly used for API servers, microservices, and BFF (Backend for Frontend) layers — not suitable for CPU-intensive workloads (video encoding, ML inference) because the single-threaded event loop blocks.