This code is used in Head First Rails from O'Reilly Media. You'll probably be able to figure out how it works by reading it, but marketing have pointed out to us that the best way of learning is by purchasing a copy of the book!1
The code here is released under an MIT License, which should allow you to use it however you want. The code is intended for learning purposes, so it doesn't have all of the bells and whistles of a full-blown GI system. But it is sufficiently simple that it should allow you to modify it for your own purposes.
Here at Head First, we love it when you mess with our code. In fact - we want it to become your code! That's why we've licensed it with a MIT license. That way you should be able to use it in whatever way is most useful for you.
So please go create - and enjoy!
1Available in all good book shops and a few disreputable ones.
