We can place Node.js modules into three categories:

• Built-in (native) modules: These are modules that come with Node.js itself; you don't have to install them separately.
• Third-party modules: These are modules that are often installed from a package repository. npm is a commonly used package repository, but you can still host packages on GitHub, your own private server, and so on.
• Local modules: These are modules that you have created within your application, like the example given previously.