Well, it’s been a wild ride since the first edition of this book was released. At that time, PowerShell had just shipped and had a fairly limited scope of influence. Things have changed a lot. PowerShell now ships in the box with Windows (at least Windows 7 and Server 2008 R2). The number of PowerShell users is now in the hundreds of thousands, if not millions (this is not a formal estimate—I just looked at some of the download counters for PowerShell-related tools and went from there).

One of the biggest events from my perspective was the release of PowerShell version 2 in July of 2009. Obviously it was time for a sequel to the book. I put together a short proposal and estimate of the amount of work needed to update the book. The initial estimate was for a few months of work—a couple of new chapters, a few updates here and there, and we’re good to go. Wow, was I ever wrong about that! PowerShell v2 was a really big release.

When you are in the middle of something, working heads down, you tend to lose perspective of the overall project—that old forest/trees problem. It wasn’t until I was preparing a talk for MMS (Microsoft Management Summit) that I realized just how BIG it was. In a one-hour talk, we barely had time to list all of the new stuff, much less describe it in detail. But describing it in detail was exactly what I needed to do and that’s why this book took a great deal longer to write than anticipated. It’s also much bigger than I had expected or wanted. At one point it was double the size of the first edition. So we cut some stuff that was no longer as relevant with PowerShell v2, moved some stuff into the online appendixes, and capped the book at about 1000 pages.

So why write the book in the first place? The answer is the same now as it was then—I wanted the PowerShell community to have a way to see “inside the box” and have a more intimate insight into the goals and motivations behind PowerShell. Although PowerShell draws heavily from existing technologies, it combines them in novel ways. This kind of novelty leads to misunderstandings which then turn into urban myths, like PowerShell does X because its designers were kitten-eating aliens. (Trust me—we’re not.)

As we showed our work to the world I found that there were a number of questions that were being asked over and over again. These questions would usually arise as a result of some prior language experience that the user had. Typically a simple explanation was all it took to clear up the confusion. Unfortunately we couldn’t keep answering these questions over and over on a one-by-one basis; that just couldn’t scale. There needed to be a way to gather this information together in one place. The book was my attempt to address that problem, and the second edition continues on with this goal.

I continue to be amazed at just how much power comes out of the synergy of the various technologies underlying PowerShell. We see this in our own internal uses of PowerShell at Microsoft as well as in what the community has done with it. And so a second goal of this book was to try and foster that creativity by conveying just how capable PowerShell is.

And finally, this is the book I wanted to read. I love programming languages and the best books are the ones that explain not only what but also why. Look at the books that continue to sell year after year: Kernighan and Ritchie’s The C Programming Language, Stroustrup’s book on C++, and Ousterhout’s book on TCL. The TCL book in particular describes a very early version of the TCL language, has never been updated, and yet it continues to sell. Why? Because these books give the reader something more than just technical detail. They convey a sense of the overall design and some element of the intent of the designer. (Let me know if I succeeded, okay?)