Why develop with Node.js ?

Node.js is a server-based open source development platform, created by Ryan Dahl in 2009. This platform uses the V8 virtual machine. Node.js is a technology that allows you to run server-side JavaScript. This language is based on events, just like JavaScript. Howevr, in practice, Node.js allows JavaScript to be operated outside the browser.

Node.js benefits from the power of JavaScript for the development of dynamic websites. This language offers many modules for performing software design through simplified software architecture.

Why is Node.js reputed to be so fast? Its power lies in two factors:

• Google V8 engine (Google Chrome runtime)
• Its non-blocking system

The main goal of Node.js is to reduce the execution time of scripts.
The technology works under the principle of separation: we use the Thread Pool library, which allows for the management of the loop of events. The platform has a standard API. The code will communicate with this API, and it will also link with the C or C ++ libraries to communicate with the system.

Node.js also has tools related to cryptography.

It is very easy to integrate an HTTP server into a Node.js application. The platform quickly becomes a particularly suitable solution for creating service APIs. In the front-end, the use of a JavaScript framework like Angular makes it possible to keep the same language and the same data format within the developed application.

As an added bonus, Node.js is also very useful for working with NoSQL databases like MongoDB (this is due to the JSON formalism which is natively compatible with JavaScript).

Node.js uses the JavaScript language of the server and allows JavaScript to be operated outside the browser. Based on the power of JavaScript, Node.js offers a new way to develop dynamic web applications.

Before the existence of Node.js, JavaScript was always used on the client side, or more precisely, on the user side that browses a web application. The user's web browser (Safari, Chrome, IE, etc.) runs the JavaScript and modifies the HTML page. In addition to the dynamization of the HTML page with JavaScript, Node.js will provide a server-side environment using JavaScript, which generates web pages. It will replace server languages ​​such as PHP or Java EE.

With Node.js, we realize the following types of applications:

• A chat server
• A document upload system
• An article reading widget
• And more.

In general, we develop an application that must be able to work well with many queries launched simultaneously.

The V8 engine

Node.js uses the V8 runtime. This engine was created by Google, and it analyzes and executes JavaScript. This execution engine is ultrafast. 
The V8 runtime performs JIT (Just In Time) compilation. V8 quickly transforms JavaScript code into machine code, then optimizes this code with processes such as inline code or copy elision.

The non-blocking model of Node.js

JavaScript is built around the notion of events and works under a code architecture that is fully non-blocking.
What is the difference between a blocking model and a non-blocking model?

With this model, the program can start performing other actions only from the moment the image is displayed.

Now let's see how a non-blocking model works with Node.js.

With this model, the program starts executing other actions as soon as event 3 "Download image" is finished. It will not wait for the "View Image" event to finish executing other actions.

This is the way Node.js works. As soon as the event "Image downloaded" appears, a function named the callback function is called and performs actions (here, the callback function will display the image).

Utilize this model in a case with a large volume of events to execute, and the saving time is considerable!

In web applications, we often have long and laborious operations to perform, such as database calls or web service calls. With Node.js, the call to a web service can be long, but you can perform other actions for the duration of the call!

As we’ve already seen, the main strength of Node.js is to be able to execute several treatments simultaneously. It should also be noted that programs are compiled before execution, which significantly improves the performance of the software.

Multiple systems

Node.js runs on Linux, Mac and Windows.

The strength of the unique language

To work on all systems: Libraries can be shared on both the server side and the client side (browser).

Package Manager: npm package

By default, the platform has a package system that allows you to quickly download and install anything. There are modules for the back end and the front end. The many contributors are very active. They improve the libraries of Node.js and go to the end of things, to the point of making a real subject in its own right called JavaScript Fatigue.

A Significant community

Node.js brought together by a strong community of passionate developers. The are many and varied media for continuous Node.Js training, including:

• Webinars
• Online course
• Mooc
• Meetup

Node.js is intended for use by scalable web applications. The popularity of this platform is growing, with the giants of the web having already experienced it: Netflix, Trello, PayPal, Walmart, Microsoft, Uber, LinkedIn, Ebay, Groupon or NASA.