Node.js

Node.js is a cross-platform JavaScript runtime environment that allows developers to write command line tools and server-side scripts outside of a browser. Node.js applications are written in JavaScript and can be run within the Node.js runtime on OS X, Microsoft Windows, and Linux. Node.js also provides a rich library of modules that can be used to create various applications.

Node.js is perfect for building highly scalable, real-time applications. Some of the biggest companies in the world use Node.js to power their sites and applications, including Walmart, eBay, Netflix, PayPal, and LinkedIn.