E stands for Express, a lightweight, minimalist framework built for Node.js. It’s been created for web applications and APIs, and comes with a myriad of HTTP facilities for the developer.
A stands for AngularJS, the Model-View-Whatever JS framework build by Google. AngularJS makes API consuming as simple as it could be, so using it as the client-side of MEAN is very helpful for every developer. Moreover, AngularJS is optimized for mobile development, so by using the same code base on the browser, you have already built a mobile app for the web application you’re developing.
N stands for Node.js, the foundation of Express. It runs on Chrome’s V8 engine and is capable of non-blocking, event-driven I/O. The Node.js application will handle multiple requests on a single service without them blocking each-other (hence non-blocking).
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