Understanding the Node.js Event Loop

The Heart of Node.js

Node.js is famous for its non-blocking, event-driven architecture. At the core of this is the Event Loop. Unlike multi-threaded languages like Java, Node.js executes code on a single thread.

How it Works

When Node.js starts, it initializes the event loop, processes the provided input script, and begins processing events. The event loop allows Node.js to perform non-blocking I/O operations by offloading operations to the system kernel whenever possible.

Understanding phases like Timers, Pending Callbacks, Poll, Check, and Close Callbacks is crucial for mastering performance optimization in Node applications.