From Node.js website
Node.js is a platform built on Chrome’s JavaScript runtime for easily
building fast, scalable network applications. Node.js uses an
event-driven, non-blocking I/O model that makes it lightweight and
efficient, perfect for data-intensive real-time applications that run
across distributed devices.
Event-driven means that the server only reacts when an event occurs. This allow us to create high performance, highly scalable, “real-time” applications.
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