"Mastering Express.js: A Comprehensive Guide to Node.js Web Development" provides an in-depth exploration of Express.js, a powerful framework for building web applications with Node.js. This book covers everything from the basics of setting up your development environment to advanced topics such as middleware, template engines, database integration, authentication, security, and real-time applications with WebSockets and Socket.io. Through practical examples and best practices, readers will learn to create scalable, maintainable, and efficient web applications, making this an essential resource for both beginners and experienced developers.