This is a book about C# from version 2 onwards -- it's as simple as that. I barely cover C# 1, and only cover the .NET Framework libraries and Common Language Runtime (CLR) when they're related to the language. This is a deliberate decision, and the result is quite a different book from most of the C# and .NET books I've seen. By assuming a reasonable amount of knowledge of C# 1, I avoid spending hundreds of pages covering material that I think most people already understand. This gives me much more room to expand on the details of C# 2, 3, and 4, which is what I hope you're reading the book for. I believe that many developers would be less frustrated with their work if they had a deeper connection with the language they're writing in. I know it sounds geeky in the extreme to talk about having a "relationship" with a programming language, but that's the best way I can describe it. This book is my attempt to help you achieve that sort of understanding, or deepen it further. It won't be enough on its own -- it should be a companion to your coding, guiding you and suggesting some interesting avenues to explore, as well as explaining why your code behaves the way it does. - Publisher.