React was built by Facebook in order to provide more structure to their code base and allow it to scale much better. React worked so well for Facebook that they eventually open sourced it. Today, React is one of the most popular JavaScript libraries for building frontends. It allows us to build small, isolated, and highly reusable components that can be composed together in order to create complex frontends.

TypeScript was built by Microsoft to help developers more easily build large frontend applications. It is a superset of JavaScript, bringing a rich type system to it. This type system helps developers to catch bugs early and allows tools to be created to robustly navigate and refactor code.

This book will teach you how you can use both of these technologies to create large sophisticated frontends efficiently that are easy to maintain.