Node.js by itself is a pretty basic system, being a JavaScript interpreter with a few interesting asynchronous I/O libraries. One of the things that makes Node.js interesting is the rapidly growing ecosystem of third-party modules for Node.js.
At the center of that ecosystem is NPM. While Node.js modules can be downloaded as source and assembled manually for use with Node.js programs, that's tedious and it's difficult to implement a repeatable build process. NPM gives us a simpler way; NPM is the de facto standard package manager for Node.js and it greatly simplifies downloading and using these modules. We will talk about NPM at length in the next chapter.
The sharp-eyed will have noticed that npm is already installed via all the installation methods discussed previously. In the past, npm was installed separately, but today it is bundled with Node.js.
Now that we have npm installed, let's take it for a quick spin. The hexy program is a utility for printing...