This chapter provided a brief overview of a topic that will be discussed in the rest of the book: design patterns. We took a look at the broader picture and found that patterns are everywhere and that design patterns are only part of a larger group of programming patterns. We also learned about architectural patterns, which function on a higher level, and idioms, which are very low-level patterns. (We will talk more about architectural patterns in Chapter 11, Other Kinds of Patterns. Delphi idioms are introduced throughout this book, starting with this chapter.)
We then learned about at the history of patterns, and were introduced to Gang of Four and their Design Patterns book. We learned that patterns are not fixed in time, but are evolving, and that many patterns, especially ones dealing with parallel programming, were documented after that book was published.
After...