If you're reading this book, you probably know what React is. If not, don't worry. I'll do my best to keep philosophical definitions to a minimum. However, this is a long book with a lot of content, so I feel that setting the tone is an appropriate first step. Yes, the goal is to learn React and React Native. But it's also to put together a lasting architecture that can handle everything we want to build with React today and in the future.

This chapter starts with a brief explanation of why React exists. Then, we'll think about the simplicity of React and how React is able to handle many of the typical performance issues faced by web developers. Next, we'll go over the declarative philosophy of React and the level of abstraction that React programmers can expect to work with. Finally, we'll touch on some of the major features of React.

Once you have a conceptual understanding of React and how it solves problems with UI development, you'll be better equipped to tackle the remainder of the book.

This chapter will cover the following topics: