1.2. Why this book?

There’s a tension in any educational book between the two extremes of pure tutorial and pure reference. We land firmly on the tutorial side of this spectrum, which has many advantages. Because our application is real, you get to learn Rails as it is actually used. You’ll see for yourself all the great ways that Rails makes writing web applications easier, from its elegant model-view-controller architecture to the brilliance of embedded Ruby. You also get the advantage of artful repetition: You see the most important ideas the most. The result is learning by osmosis.

In the process of building RailsSpace, we’ll also see how Rails makes it easy to write automated tests to make sure our application does what we wanted it to do. Because of our tutorial approach, we will be able to develop the tests incrementally in parallel with the application, just as you do (or should do) in real life. As our application evolves, you’ll see how great having a test suite is: Whenever we modify a feature or add a new one, we can run the tests to make sure that we haven’t broken some other part of the application.