The first edition of The Principles of Beautiful Web Design hit the shelves in late February of 2007. Considering that I started writing the first chapter in May of 2006, much of the content is now over 4 years old. That’s a long time, and when we’re talking about web design, that’s a *really* long time. In fact, there’s not a single screenshot example in the book that hasn’t changed significantly since it was first published.

In defiance of its age though, the book has continued to be one of Sitepoint’s bestselling titles and sold over 10,000 copies during the second half of 2009 alone. How could a tech book, nearly 3 years past its prime continue to sell? Well, it’s not really a tech book…