Modules (CommonJS vs ESM)

Summary

Node's two module systems — the original `require`/`module.exports` (CommonJS) and the newer standard `import`/`export` (ES Modules) — with different loading behavior and syntax.

How to Learn This

1Write the same small module in both CommonJS and ESM syntax.
2Learn how to enable ESM in a Node project (`"type": "module"` in package.json).
3Understand why CommonJS is synchronous and ESM is asynchronous under the hood.

Non-Blocking I/O

NPM & Package Management

More topics in Node.js Fundamentals

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

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