Even though we assume that the reader of this book is not a Design Pattern Denier, it's still a very good idea to remind ourselves why design patterns exist and why a successful framework such as Qt makes extensive use of different design patterns. Well, first of all, a design pattern is just one of many solutions to a software development task and it is not the only solution; and in fact, most of the times it's not even the fastest solution. However, a design pattern is definitely the most structured way of solving a software development problem, and it helps make sure you use some predefined template-like structures for everything you add to your program.
Design patterns have names applied to different kinds of problems ...
