Event Emitter

Summary

Node's built-in pattern for building objects that emit named events other code can listen for — the mechanism underlying HTTP servers, streams, and much of Node's core API.

How to Learn This

1Build a simple custom class extending `EventEmitter` that emits a custom event.
2Learn `.on()`, `.once()` and `.emit()`.
3Recognize that Node's `http.Server` and streams are themselves EventEmitters.

Process & Environment Variables

Child Processes

More topics in Node.js Fundamentals

Node.js Runtime V8 Engine Event Loop Non-Blocking I/O Modules (CommonJS vs ESM)NPM & Package Management package.json Async Programming Callbacks Promises Async/Await Streams Buffers File System (fs)Process & Environment Variables Child Processes Clustering

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