Installing node.js

Let's not delay any further and install node on your computer. How to install it will be different depending on the OS you are running. Go to http://nodejs.org/ and get the proper download. The result is the same everywhere: it gives us two programs: node and npm.

npm

npm, the node packaging manager, is the tool that you use to look for and install modules. Each time you write code that needs a module, you specify this by putting something like the following in your code:

var module = require('module');

It will have to be installed if it is not yet present, using the command:

npm install

Or you can also use:

npm -g install

The latter will attempt to install the module globally, the former command in the directory where the command is issued. It will typically install the module in a folder called node_modules.

node

The node command is the command to use to start your node.js program, for example:

node myprogram.js

Node will start and interpret your code. Type Ctrl...