What Is Node.js & How Does It Work?

Node.js is a free, open-source server environment that’s often used for dynamic content generation and data modification. It’s compact and efficient, making it a great choice for real-time environments, and it can run across multiple platforms including Linux, Unix, Mac, Windows, and OS X.

But what does this mean in practice? What does Node.js do in the context of your IT environment, and how does it work to deliver desired outcomes? More importantly, where is Node.js useful to help streamline application functions?

Read on to find out, or hit the jumplinks for quick answers to common Node.js questions.

• What does Node.js do?
• How does Node.js work?
• Where is Node.js useful?
• Why use Node.js?

What does Node.js do?

Node.js is a runtime environment that allows you to run JavaScript outside the confines of a browser.

This means it’s not a programming language or a framework for developing applications. Instead, Node.js is an environment that helps facilitate the use of programming languages and frameworks.

As a result, Node.js can be used for both frontend and backend development.

What languages are Node.js written in?

Node.js is written in JavaScript, C, and C++. It also uses the Chrome V8 JavaScript execution engine, along with a libuv platform abstraction layer. The first Node.js version was written in 2009 by software engineer Ryan Dahl.

How does Node.js work?

Node.js uses what’s known as single-threaded, non-blocking, asynchronous programming.

This allows the runtime environment to efficiently process requests and deliver responses in near real-time. Consider a file request. Under a PHP or ASP framework, requests are sent to the file system while ASP or PHP waits for the response. Once received, the content is returned and the system is ready for a new task.

Node.js does things differently. Instead of waiting for the file system to find and open the file, Node.js sends the task and then moves on to the next request.

This is possible thanks to the “non-blocking” nature of Node.js. Here’s how it works: When a request comes in, Node.js sends it to a continuously running “Event Loop”. The loop then determines if the request requires blocking input/output operation. If not, the request is processed immediately. If so, the task is placed into a queue for completion, ensuring that blocking-based tasks run sequentially rather than in parallel.

Where is Node.js useful?

Thanks to its open-source, non-blocking nature, Node.js is scalable, easy to use, and simple to maintain. As a result, it’s useful in multiple scenarios, such as:

IoT Connections

Internet of Things (IoT) deployments leverage multiple devices and sensors to collect small amounts of data and combine them to create a cohesive whole. Node.js is a great choice to handle high-volume, concurrent data requests.

Data Streaming Frameworks

Node.js also excels at data streaming thanks to the inclusion of a native streaming API and its ability to directly pipe data requests from user to user.

Single-Page Applications (SPAs)

SPAs leverage background requests to deliver app functionality on a single page. The non-blocking nature of Node.js makes it easy to handle these requests without impacting performance.

Consider a quick Node.js example. Let’s say you’re looking to create a simple with the content “Node.js is great”. The code looks like this:

 
var fs = require('fs');
var data ='Node.js is great';

// writeFile function with filename, content and callback function
fs.writeFile('newfile.txt', data, function (err) {
if (err) throw err;
console.log('File is created successfully.');
});

There are also situations where Node.js may not be your best choice. For example, if you’re running multiple, data-intensive tasks you may be better served with a multi-threaded language such as Java. If you’re looking for a quick response that limits compute conflicts, meanwhile, consider Node.js.

Why use Node.js?

Node.js makes it possible to quickly process dynamic content requests and return them in near real-time. As a result, it’s a great choice to help streamline JavaScript code execution.