Node.js is a cross-platform run-time environment for executing applications written in JavaScript. It was built when the creators of JavaScript needed to extend it from browser-only to building standalone applications.
It has allowed Nodejs developers to create applications with two-way (client-server) connections in real-time, where the data exchanges are virtually unlimited. It can handle an astonishing number of connections at the same time.
This means that Node.js isn’t universal, but it solves a particular problem. It’s not a good platform for solving large computational issues. However, the unique architecture of Node.js makes it great for creating easily scalable, fast network applications in JavaScript.
Many high-profile companies use Node.js, like Walmart or Uber, even institutions like NASA.
The main difference between Node and other web servers is that traditionally, a web server has to open a new connection for every request, blocking other incoming connections. Because of that, scaling a typical server requires launching additional servers.
Node.js, on the other hand, is driven by events. This means that it can handle much more requests at a time, and it makes Node fast, and easily scalable.
Some say that it works best for web applications which need a stable connection between the server and the user, like online games or chat software.
It’s open-source, and a whole ecosystem has grown around it. Developers constantly create new modules and packages for others to use in specific situations. These add-ons can be found in the node package manager (npm), an open library of JavaScript projects.
This means a different workflow for developers using Node.js. There are packages for almost any situation in the npm, so the first thing that a good developer will do is find, and implement the right packages to save development time.