Architects of buildings and architects of software have more in common than most people think. Both professions require attention to detail, and both practitioners will see their work collapse around them if they make too many mistakes. It's impossible to imagine a world in which buildings get built without blueprints, but it's still common for software applications to be designed and built without blueprints, or in this case, design patterns. A software design pattern can be identified as "a recurring solution to a recurring problem." Using design patterns for software development makes sense in the same way that architectural design patterns make sense--if it works well in one place, why not use it in another? But developers have had enough of books that simply catalog design patterns without extending into new areas, and books that are so theoretical that you can't actually do anything better after reading them than you could before you started.