Each module in NodeJS has its own context and cannot interfere with other modules. Modules are like libraries that you can include in your application. Node.js has a set of built-in modules you can use without any further installation, such as http, fs, path, and url.
Express is a minimal and flexible Node.js web application framework that provides a robust set of features for web and mobile applications. Explore how to set up a web application quickly with Express.