James Hibbard - Node.js: The Collection

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So youve heard of Node.js, but arent quite sure what it is or where it fits into your development workflow. Or maybe youve heard people singing Nodes praises and now youre wondering if its something you need to learn. Perhaps youre familiar with another back-end technology and want to find out whats different about Node.

If that sounds like you, then keep reading. In this article Ill take a beginner-friendly, high-level look at Node.js and its main paradigms. Ill examine Nodes main use cases, as well as the current state of the Node landscape, and offer you a wide range of jumping off points (for further reading) along the way.

There are plenty of definitions to be found online. Lets take a look at a couple of the more popular ones:

This is what the projects home page has to say:

Node.js is a JavaScript runtime built on Chromes V8 JavaScript engine. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient.

And this is what StackOverflow has to offer:

Node.js is an event-based, non-blocking, asynchronous I/O framework that uses Googles V8 JavaScript engine and libuv library.

Hmmm, non-blocking I/O, event-driven, asynchronous thats quite a lot to digest in one go. So lets approach this from a different angle and begin by focusing on the other detail that both descriptions mention the V8 JavaScript engine.

The V8 engine is the open-source JavaScript engine that runs in the Chrome, Opera and Vivaldi browsers. It was designed with performance in mind and is responsible for compiling JavaScript directly to native machine code that your computer can execute.

However, when we say that Node is built on the V8 engine, we dont mean that Node programs are executed in a browser. They arent. Rather, the creator of Node (Ryan Dahl) took the V8 engine and enhanced it with various features, such as a file system API, an HTTP library, and a number of operating systemrelated utility methods.

This means that Node.js is a program we can use to execute JavaScript on our computers. In other words, its a JavaScript runtime.