Welcome to your first lesson in Back-End Engineering with Express.js! Today, we're going to dive into the world of server-side development, a critical component of any web application. By understanding and setting up a basic Express.js server, you'll unlock the door that allows user browsers and your web application to communicate.

Express.js is a lightweight and efficient web application framework for Node.js that's loved by developers worldwide. It's perfect for building web applications and APIs, serving as the back-end part of the MEAN stack — namely MongoDB, Express.js, AngularJS, and Node.js. You'll get a lot of hands-on practice throughout this course. Remember, all the necessary libraries, like Express.js, are pre-installed on the CodeSignal IDE, so you don't need to worry about installation for now.

By the end of this lesson, you will be able to set up an Express.js server from scratch, understand how it operates, and see it in action.

Are you excited? Let's get started!

Just as human societies cannot function without rules and structures, web development requires frameworks to organize code and streamline development. One such framework is Express.js, used for building web applications on top of .