In this chapter, we went through a quick overview of Node.js, seeing how it looks under the hood.

We wrote basic Node.js code and ran it from the Terminal using the Node.js command.

We also looked at module system of Node.js, where we learnt about the three categories of Node.js modules, that is, in-built, third-party (installed from the npm registry), and local modules, and their examples. We also looked at how Node.js resolves a module name whenever you require it, by searching in the various directories.

We then finished off by looking at the asynchronous programming model that is at the heart of how Node.js works, and what actually makes Node.js tick. We looked at the three main ways you can write asynchronous code: using callbacks, Promises, and the new async/await paradigm.

The foundation is now laid for us to go ahead and implement our API using Node.js. Most of these concepts will crop up again as we build our API.