Angular CLI is the command-line interface tool that helps you kickstart new projects and maintain your application using best practices while you're creating different components of Angular, and also lets you test these practices. It also allows you to build for production and serve the application for development with its live reloading capability, along with the ability to lint, test, and run end-to-end (e2e) test cases. This project is open source and is maintained by the Angular team. Because of its wide use in the Angular community—apart from making life easier while developing an application—if you were to encounter a new Angular app that uses Angular CLI, it would follow the same shape. We will be using Angular CLI to create Angular applications and add additional functionality as and when required.