This book serves as a succinct guide on ReScript, a functional language for building web applications. Using examples of ReScript language features along with explanations of fundamental concepts in functional programming, this book will show web developers with a background in JavaScript how to effectively use ReScript to its full potential. In Introducing ReScript, you'll learn how to use features in ReScript that JavaScript lacks, such as type inference, null-safety, algebraic data types, pattern matching, and more. Along the way, you'll pick up functional programming concepts like immutability and higher-order functions. You'll also gain a sense of how ReScript works under the hood and how to leverage interoperability between ReScript and JavaScript. Whether you're a web developer interested in dabbling with functional programming or you just want to learn how to write safer and cleaner code for web applications, this book is a great way for you to get started with ReScript. What You Will Learn Use ReScript to write clean, safe, and elegant software Understand the features of ReScript that set it apart from JavaScript, such as type inference, null-safety, and algebraic data types Explore functional programming concepts like immutabhigher-orderr order functions, and pattern matching Use popular JavaScript libraries and frameworks in your ReScript code and integrate ReScript code into JavaScript codebases Who This Book Is For Web developers that want a strictly typed, safer alternative to JavaScript, as well as web developers interested in learning functional programming and leveraging the elegant and powerful functional features in ReScript.