Node.js is a go-to backend technology for modern startups due to its speed, efficiency, and scalability.It is built on Google's V8 engine, which compiles JavaScript directly to machine code, offering fast execution.With a unified tech stack using JavaScript on both frontend and backend, Node.js enables faster development cycles.Node.js supports real-time capabilities and is suitable for use cases like messaging apps, SPAs, RESTful APIs, and e-commerce backend systems.