API design is complicated. After all, if it were easy there would probably be little need for this book at all. But before we start exploring the tools and patterns to make API design a bit more manageable, we first have to agree on some fundamental terminology and what to expect from this book. In the next two chapters, we’ll cover some of the introductory material that will act as a platform for us to build on throughout the rest of the book.
We’ll start in chapter 1 by defining in detail what we mean by an API. More
importantly, we’ll investigate what good APIs look like and how to distinguish
them from bad APIs. Then in chapter 2, we’ll look more closely at what we mean
by a design pattern and the anatomy of the patterns outlined in the rest of the
book, with the end goal of relying on these design patterns to build consistently
good APIs.