JavaScript on the server; let that sink in for a moment….
What is Node.js? The quick and dirty answer is that it's a unique and very fast server environment to handle requests from client applications and apps that are authored in Javascript. It's Javascript on the server. More specifically, it's an I/O framework that:
Is event-driven
Is nonblocking
Runs on the V8 JavaScript engine
Executes JavaScript code on the server side
Is rich in robust developer libraries and modules
Node's speed makes it particularly useful in physical computing scenarios as it can handle requests in real time. After all, when a gust of sudden wind blows and your BBB-powered drone starts teetering midair, you don't want to rely on a poky LAMP stack and keep those gyros compensating.
The good news about Node.js—and we'll often just call it node—is that you don't have to install it because it comes preloaded on the BBB firmware. The bad news about Node.js is that it can be a bit confusing to understand...