Node.js is known for its asynchronous, non-blocking I/O model, which relies heavily on the event loop. This article explains how the Node.js event loop works, including phases like timers, I/O callbacks, idle, poll, and check. It also explores how callbacks, promises, and async/await integrate with the event loop, and how developers can avoid pitfalls like blocking the event loop or callback hell. Understanding this concept is crucial for building high-performance backend applications.