Book excerpt: This book is a quick and useful guide to learning the reactive programming in Angular through step-by-step pictorial tutorials that are easily understood by beginners. It covers four important packages, including @NgRx/Store, @NgRx/Entity, @NgRx/Effects, and RxJS for developing large-scale reactive projects. Features in these four packages are covered thoroughly in this book with hands-on examples that allow readers to become experts in creating scalable and extendable web applications. What This Book Covers？ Chapter 0, Getting Started with Angular NgRx, covers setting up an environment for developing Angular NgRx applications. If you are familiar with the development of the web application with Angular, please skip this chapter. Chapter 1, Reactive Programming in Angular for Beginners, develops a web application for beginners to Angular NgRx. We simplify the example in this chapter to focus on the basic and important concepts about the store and the relationship between a store and components and help beginners to grasp the main ideas in this chapter. Chapter 2, Communication between Two Components, evolves the concepts of the store, which shows how two components talk via a centralized store. Chapter 3, Nested Store Data Structure, manipulates the complicated data structure of states, introduces the concept of payload, and demonstrates how to select data from states with different levels. Chapter 4, Build Hierarchical Module, State, and Reducer, investigates how to build scalable and extendable projects with hierarchical modules, states, and reducers. It shows how @NgRx/Entity automatically generates code with functions of creating, retrieving, updating, and deleting data (CRUD). Chapter 5, Retrieve the Store with Selectors, continues to discuss how to retrieve data based on @NgRx/Entity and how to mimic the functions of SQL SELECT with selectors. Chapter 6, Introduction to RxJS, walks you through creating, filtering, transforming, and manipulating observables which are streams of data. RxJS is an important tool to create reactive applications and help you understand the next chapters. Chapter 7, Injectable Action Listener, Processor, and Dispatcher, explores @NgRx/Effects which listen to actions and perform the function of logging. Chapter 8, Handling HTTP Requests with Effects, demonstrates the interactions among servers, services, effects, stores, and components through a stock view web application.