Node.js is a JavaScript runtime environment and it’s built on Chrome’s V8 JS engine.

Historically, JavaScript was used mainly for client-side scripting and it ran the client-side by a JS engine in the user’s web browser. In practice, this meant that the server-side required a different programming language, which often translated into hiring different developers to do the frontend and the backend. Node.js aimed to extend that to something that could run a standalone application. This gave JavaScript the capabilities similar to those that other languages like Python have.

As the description of Node.js says:

Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient.

Node.js’ package ecosystem, npm, is the largest ecosystem of open source libraries in the world.

But what does that mean, exactly?

I/O means input/output operation. It can refer to a whole variety of things, like making an HTTP request to API or reading the file contents. Non-blocking means that the application is running asynchronously, so the parser doesn’t wait to execute the whole application code from the beginning till the end and can handle many tasks in one thread. In other words, when the application sees that it will wait for data from another component (i.e. database), it puts the waiting task in a waiting queue and takes another item from that list to process it in the meantime, at the same time minimizing delays and increasing efficiency.

It’s difficult to put a label on Node.js. Why? Its definition is quite complex (just see above) and there’s no shortcut you can take, really.

It’s not a programming language dedicated to developing backend web apps – but it utilizes one of the most popular ones.

It’s not a framework, nor a library, but there are JavaScript frameworks built specifically to run on Node.js environment, such as Express.js.

It’s not a package manager by itself, but it tightly works with and relies on them, and what is even more important, we have many options to choose from – such as npm or bower.

All the technical wonders of Node.js are impressive, but we can also sum up its advantages in a few words: it’s fast, lightweight, scalable, and efficient. And what more could you ask for?

A comprehensive guidebook for startup founders

When, how and why use Node.js for your backend


What types of applications can be built with Node.js?

A lot of big players are already team Node. Netflix, Uber, PayPal… Just to name a few (more on that later – stay tuned!). Node is not limited to a list of apps that you can make with it. Whenever you start developing a software product, you shouldn’t only think about what’s in fashion or not (though the Node hype is here for a reason), but you should get expert advice on what technology will be best for your product. There are a few things that make Node.js stand out and take the lead when we compare it to other alternatives.

Read also: Using Node.js for back-end development

First of all, Node provides fast delivery. Remember the lean startup thing we’ve mentioned in some of our previous articles (for example: Why do you need innovation workshops)? We deeply believe that it works. Delivering functioning pieces, or prototypes, and testing the concepts is crucial to the development. Node.js helps achieve that in a few ways. It can share whole code modules and tests between the client (e.g. browser) and server, which comes in handy. Also, there’s no huge struggle with communication with backend and frontend. Same language and same approach to handle JSON covers it all. Sure, these may not be huge things, but everything time-saving matters in the development process.

Secondly, applying changes can be done easily and quickly. Node’s event-driven model handles substantial changes efficiently.

Last, but not least, comes the scalability. You want your product to be scalable both in terms of business and technology. It’s hard to say whether Node is more scalable than PHP or Ruby, but it definitely is really easy to scale, thanks to its popularity and support in the community.

OK, but let’s get to the apps.

Real-time chats

Real-time communication is one of the applications you can build with Node.js

A real-time chat is any type of communication tool that enables real-time exchange of text messages, voice or video calls, etc. These can be one to one or group chats in IM (instant messaging) or IRC (Internet Relay Chat) technologies. Real-time chats are widely popular anywhere on the internet – especially with the giant popularity of social networking apps.

Node.js is the perfect solution for real-time chats. The asynchronous nature of this runtime brings powerful Event API that allows us to work in event-driven approach almost with any data. This functionality clears the way for implementing server-side events and push notifications that are common in real-time communication applications. Node’s architecture works well with the WebSocket protocol, which is important for the fast exchange of messages between the client and the server via a single open connection. If you implement WebSockets both on the client and the server side, you can create real-time messaging with faster data transfer and lower latency.

Single-Page Applications

A single-page application (SPA) is a web app that fits into one page. It rewrites the current page (or even fragment of that page) instead of loading new pages from the server. SPAs are commonly used e.g. in social media platforms. Since Node.js handles asynchronous calls and heavy I/O workloads efficiently, it is well-suited for SPAs. Utilizing Node’s approach to efficiently handle many things at once, it is a perfect condition to fulfill many requests with small chunks of data sent often to the front-end application. This means that what the user sees transitions in a way that is subtle and consistent so that the user doesn’t have to wait to interact with the app.

Additionally, most SPAs use frameworks such as Angular, Meteor, Vue, or React – all JavaScript frameworks. As Node.js is also written in JavaScript, developers can use the same data and language structure on the server and the client side. This speeds up the development and makes the SPA easier to maintain.

Streaming applications

Application streaming, as described in Wikipedia, is a “form of on-demand software distribution”. This means that only some essential elements of the app have to be downloaded and installed on the device, all other parts can be downloaded later when they’re needed. This can bring users to the application quickly, without letting them wait until the download of the huge amount of data is done. You could ask: Where’s Node’s advantage in this? Node handles data streaming extremely well. It achieves that by having many tools built exclusively to handle, monitor, and process streams, and by doing that efficiently. All of that contributes to an excellent environment to work with streaming data.

Collaboration tools

There’s a whole variety of collaboration tools available on the market: Trello (and other) for project management, Google Docs for collaborative editing of documents, Hangouts for conferencing. These and many more tools make it possible for a team to share a workspace and collaborate even if they don’t work in one office. Or even one country for that matter. All of these collaboration tools are real-time, so (similarly to real-time chats) Node’s asynchronous and event-based architecture plays a significant role. Again, many events and requests occur at the same time – multiple users can be editing the same file, moving tasks between the boards in Trello, commenting, adding media files. Node’s WebSockets and event API make sure that the operations performed by multiple users do not negatively impact the server and that all server-side data is delivered back to the client with no delay. Node’s role is to ensure that all of the users see the same view, with all the updates applied.

Internet of Things

The Internet of Things (IoT) is anything that connects to the internet and shares data. These can be sensors, beacons, and many more – as long as the device exchanges data and shows information in an electronic form. The normal transfer of data in IoT is from the device to the server and from the server to an app which can process the information and display it to the user. The importance of Node.js here lies in the fact that it allows the processing of multiple concurrent requests and a vast number of devices (even millions!) on the network. Node’s event-driven architecture and asynchronous processing helps process all the requests and doesn’t block Node’s servers. Node.js constitutes an efficient application layer between the IoT devices and the databases that store the information gathered from these devices.

Is there more?

As you can see, the list of Node’s advantages is quite extensive. If the app you want to build needs to handle multiple concurrent requests, heavy I/O workloads or frequent data shuffling, Node.js is definitely the right choice for you. But then again: explore your options, ask for expert advice. You should not choose the technology first and then hire accordingly. The first step is to find the actual best technological match. Experienced developers will guide you and help you find what’s best. Don’t follow trends, follow your objectives.

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