Agile Web Development with Rails (4th edition)

Ruby on Rails helps you produce high-quality, beautiful-looking web applications quickly. You concentrate on creating the application, and Rails takes care of the details.
Tens of thousands of developers have used this award-winning book to learn Rails. It's a broad, far-reaching tutorial and reference that's recommended by the Rails core team. If you're new to Rails, you'll get step-by-step guidance. If you're an experienced developer, this book will give you the comprehensive, insider information you need.
Rails has evolved over the years, and this book has evolved along with it. We still start with a step-by-step walkthrough of building a real application, and in-depth chapters look at the built-in Rails features. This edition now gives new Ruby and Rails users more information on the Ruby language and takes more time to explain key concepts throughout. Best practices on how to apply Rails continue to change, and this edition keeps up. Examples use cookie backed sessions, HTTP authentication, and Active Record-based forms, and the book focuses throughout on the right way to use Rails. Additionally, this edition now reflects Ruby 1.9, a new release of Ruby with substantial functional and performance improvements.