This book aims to help JavaScript developers who have zero-to-some experience with the MERN stack to set up and start developing web applications of varying complexity. It includes guidelines for building out and running the different applications supplemented with code snippets and explanations of key concepts.

The book is organized into five parts, progressing from basic to advanced topics, taking you on a journey of building MERN from the ground up, then using it to develop different applications with simple to complex features, while demonstrating how to extend the capabilities of the MERN stack based on an application's requirements.

Chapter 1, Unleashing React Applications with MERN, and Chapter 2, Preparing the Development Environment, set the context for developing web applications in a MERN stack and guide you through setting up your development environment.

Chapter 3, Building a Backend with MongoDB, Express, and Node, and Chapter 4, Adding a React Frontend to Complete MERN, show you how to bring the MERN stack technologies together to form a skeleton web application with minimal and basic features. Chapter 5, Growing the Skeleton into a Social Media Application, demonstrates how this skeletal MERN application can act as a base and be easily extended to build a simple social media platform. This ability to extend and customize the base application will be employed with the other applications developed in the rest of this book.

In this part, you will become more familiar with the core attributes of a MERN stack web application by building out two real-world applications—a web-based classroom application in Chapter 6, Building a Web-Based Classroom Application, and a feature-rich online marketplace in Chapter 7, Exercising MERN Skills with an Online Marketplace, Chapter 8, Extending the Marketplace for Orders and Payments, and Chapter 9, Adding Real-Time Bidding Capabilities to the Marketplace.

Chapter 10, Integrating Data Visualization with an Expense Tracking Application, Chapter 11, Building a Media Streaming Application, Chapter 12, Customizing the Media Player and Improving SEO, Chapter 13, Developing a Web-Based VR Game, and Chapter 14, Making the VR Game Dynamic Using MERN, demonstrate how this stack can be used to develop applications with more complex and immersive features, such as data visualization, media streaming, and virtual reality (VR) using React 360.

Finally, Chapter 15, Following Best Practices and Developing MERN Further, wraps up the preceding chapters and applications developed by expanding on the best practices to follow to make successful MERN applications, suggesting improvements and further developments.

You may choose to use the book out of the prescribed order based on your experience level and preference. A developer who is new to MERN can follow the path set out in the book. For a more seasoned JavaScript developer, the chapters in the Building MERN from the Ground up section would be a good place to start setting up the base application, then pick any of the six applications to build and extend.

This structure is set out with the intention to enable hands-on learning for developers from varying backgrounds. In order to maximize this intent, we recommend a practical approach for following along with the material in the book, as described in more detail in the next section.