what i found in safaribooksonline
Get ready to take a trip to a foreign country. It's time to visit Objectville, a land where objects do just what they're supposed to, applications are all well-encapsulated (you'll find out exactly what that means shortly), and designs are easy to reuse and extend. But before we can get going, there are a couple of things you need to know first, and a few language skills you're going to have to learn. Don't worry, though, it won't take long, and before you know it, you'll be speaking the language of OO like you've been living in the well-designed areas of Objectville for years.